Spelling for Scientists and Lab Staff: Terms That Go Wrong in Papers

The experiments were careful, the statistics are sound, the figures are clean. Then the reviews come back, and one of them includes a line you were not expecting: "The manuscript contains a number of spelling errors, including in the figure legends." You search, and there it is. Flourescence, three times, in the one part of the document the spell-checker never looked at.

Scientific writing is dense with words that are long, rare, and assembled from Greek and Latin parts, and most of them were never taught at school. Scientists tend to learn them by ear in the lab and by eye in the literature, rather than by ever having to produce them letter by letter. The result is that people with years of training and real expertise go on misspelling a small, stubborn set of terms for their entire careers.

This guide is for anyone who writes papers, protocols, theses, reports or lab notes. It covers why spelling matters more in science than people like to admit, the roots that make hard terms easy, and the plurals that catch careful writers. Then come fifty terms worth checking, the British and American question as journals actually handle it, and a short routine that catches most errors before a reviewer does.

Why spelling matters in science

There is no good evidence that a few typos alone sink a strong paper. Editors and reviewers judge the science first. But reviewers notice, and many say so in their reports, and some will read careless writing as a hint of careless work. That inference is unfair. It is also human, and a clean manuscript simply removes it from the table.

In a protocol the stakes are higher, because someone will act on what you wrote. Many chemical names differ by one or two letters: nitrate and nitrite are different compounds, as are sulfate and sulfite, ethanol and ethanal, hexane and hexene. In clinical work, hyperkalemia and hypokalemia mean opposite things. A spell-checker will pass every one of them, because every one is a real word.

Then there is findability. Search tools and databases match the exact letters you give them, and a misspelled gene, species or method can make a paper invisible to the people most likely to cite it. The letters in science also carry data, which is where things can go badly wrong. In 2016, Mark Ziemann, Yotam Eren and Assam El-Osta examined papers that shipped gene lists as Excel supplementary files, and reported in Genome Biology that roughly a fifth of them contained corrupted gene names. The spreadsheet had silently converted them into dates or numbers, so that a gene called SEPT2 became 2-Sep. The problem was persistent enough that the committee responsible for human gene names later renamed the affected genes. Getting the letters right is not cosmetic.

Why expert writers still misspell technical terms

Knowing a word and spelling it are different skills, and they live in different places. Reading asks you to recognize a word on the page; spelling asks you to build it from memory, in order, with nothing to look at. You can read fluorescence a thousand times without ever being forced to decide whether the u comes before the o.

Science adds three traps of its own. Many terms were first learned by ear, in fast lab conversation where vowels blur. Many come from Greek or Latin and use letter combinations that ordinary English rarely does, like the ae in larvae or the cc in desiccate. And many resemble everyday words closely enough to pull your hand the wrong way: flour hides inside a common misspelling of fluorescence, and homogenous looks like a perfectly reasonable way to spell homogeneous.

The remedy is not embarrassment. It is to learn the handful of roots and patterns behind the recurring errors, and to deliberately drill the few terms that are your own personal weak spots.

The roots behind the hard words

Most difficult terms become easy once you see their parts, because each part has a meaning and the meaning dictates the letters.

The word fluorescence begins with the mineral fluorite, used historically as a flux to help ores melt and flow, whose name comes from the Latin fluere, "to flow." In 1852 the physicist George Gabriel Stokes named the glow he observed in fluorite fluorescence. So the word starts with fluor, as in fluorine and fluoride, and never with flour. It ends in -escence, with the sc you also find in adolescence and luminescence.

A centrifuge is centri, "center," plus fuge, "to flee": things flee the center. The same fuge appears in refuge and fugitive. The verb desiccate means to dry out, from the Latin siccus, "dry," so it has one s and two cs: de-sic-cate, desiccator, desiccant.

An aliquot comes from a Latin word meaning "some" or "several," and it ends in -quot, like quota. Its verb forms appear as both aliquoted and aliquotted; pick one per document and hold to it. The term supernatant is super, "above," plus a root meaning "swimming," and it ends in -ant, not -ent.

Finally, homogeneous has an e before its ending, homo-gene-ous, "of the same kind." The shorter homogenous was once a distinct term in biology, and many dictionaries now list it as a variant, but most science editors still expect homogeneous, and the same goes for heterogeneous.

Greek and Latin plurals

This is where careful writers slip most often, because the errors look like grammar rather than spelling. "This criteria" uses a plural as a singular; "these phenomenon" does the reverse. Both appear in published papers with depressing regularity.

The patterns are simpler than the list makes them look. Greek -is becomes -es, as in hypothesis and hypotheses. Greek -on becomes -a, as in criterion and criteria. Latin -um becomes -a, as in bacterium and bacteria. Latin -us often becomes -i, as in nucleus and nuclei, and Latin -a becomes -ae, as in larva, larvae, alga and algae.

A few words have two accepted plurals. Formulae and formulas are both in use, as are indices and indexes. Data is historically the plural of datum, and journals divide on whether to write "the data are" or "the data is." Check the house style and be consistent; the guide to plurals that trip everyone up covers the wider rules.

Fifty terms worth checking

These terms go wrong often in papers, theses and protocols. They are grouped by type, so check the rows that match your field.

Some notes on these. The verbs liquefy and rarefy end in -efy rather than -ify, which surprises almost everyone. Phosphorus is the element; phosphorous, with -ous, is an adjective used in a few compound names such as phosphorous acid. The adjective negligible ends in -ible. Species names are a trap of their own: cerevisiae has an i before its ae, and Caenorhabditis contains two vowel pairs most people have never had cause to type. The genus takes a capital and the species does not, and both are italicized.

For the confused pairs, dependent is the adjective in both British and American English, while dependant, with an a, is a British noun for a person who relies on someone else. Discrete means separate, as in discrete variables, and discreet means tactful. The guide to affect, effect and forty other confused pairs settles the rest with examples.

British or American: which spelling for your journal?

There is no single rule in science. Each journal chooses. Some use American spelling, with color, behavior, analyze, hemoglobin and estrogen. Others use British spelling, with colour, behaviour, analyse, haemoglobin and oestrogen. Some use British spelling with -ize endings, a style known as Oxford spelling. The author guidelines will say which.

Chemistry adds a layer. IUPAC, the body responsible for chemical nomenclature, uses sulfur and aluminium, and many British journals have adopted sulfur to match, while many American journals keep aluminum. Again, the journal's guide wins. The major style manuals are useful references here: the ACS Style Guide for chemistry, the AMA Manual of Style for medicine, and the Council of Science Editors' Scientific Style and Format for the sciences generally.

The error to avoid is mixing, because analyse in the abstract and analyze in the methods looks careless even to a reader who has no view on which is correct. Set your word processor's language to match the journal before you start, and at the end search the draft for the other variety. The guide to British and American spelling lists the main pairs.

Protocols: write for a tired reader

Picture the person who will use your protocol. It is early, they are tired, they have gloves on, and they will read one line, do one step and read the next. They will not stop to wonder what you meant.

So write short steps with one action each. Spell every reagent in full at first mention, with its exact name, and do not rely on abbreviations only your own lab uses. Where two reagents differ by a letter, say so in the step itself: "Use sodium nitrite, not nitrate." It feels excessive. It is not.

Check units as closely as words. A slip between mL and µL is a spelling error too, and it is off by a factor of a thousand. Before anyone else uses a new protocol, read it aloud once, or better, ask a colleague to follow it while you watch. Every place they pause is a place that needs fixing.

A routine that catches errors before a reviewer does

Most spelling errors survive into submitted papers for one of three reasons. They are real words, so the spell-checker passes them. They sit in figures, tables and captions that the spell-checker skips. Or they are technical terms the checker does not know, so the writer learns to ignore its red lines altogether. A twenty-minute routine deals with all three:

1. Keep a list of your project's key terms, including species, genes, compounds and methods, and verify each once against an authoritative source such as NCBI Taxonomy or PubChem.
2. Add those verified terms to your word processor's custom dictionary, and only once you are sure of them.
3. Before submitting, search the draft for known misspellings such as flour, homogenous, seperate and occurence.
4. Read every figure legend, table and axis label on its own, slowly, aloud if you can.
5. Search for both spellings of any word your journal is strict about, such as analyse and analyze.

Reading aloud matters more than it sounds. It slows you down and forces your eyes onto each word rather than the word you expect, which is how most people catch nitrate written where nitrite was meant.

Learning the terms so you stop needing the list

A routine catches errors. Learning the words prevents them, and the evidence on how to do that is clear and simple. Testing yourself beats rereading: Henry Roediger and Jeffrey Karpicke showed in 2006 that retrieving material from memory produced far better retention than studying it again. Spacing beats cramming: a review of hundreds of studies by Nicholas Cepeda and colleagues, also in 2006, found that practice spread over time consistently outlasts the same practice massed together.

In practice, take the ten terms you get wrong most, write them from memory for five minutes, check them, and repeat after two days and again after a week. Most people find their personal problem list is short, and owning it takes a few weeks. If you would like a tool to manage the timing, Spelling.School reads each word aloud, shows which letters went wrong, and schedules words for review with spaced repetition; it also has word lists for several careers.

Your next step

Before you next submit a paper, run the five-step routine on the draft and write down every term it catches. That list, practiced from memory for a few minutes a week, is the fastest way to stop the same errors coming back. For the broader workplace errors that make any professional look careless, the list of spelling mistakes that make you look unprofessional is a useful companion.

Questions people ask

What science words are most commonly misspelled?

Some of the scientific terms most often misspelled are fluorescence, desiccator, homogeneous, supernatant, occurrence, liquefy and centrifugation. Greek and Latin plurals such as hypotheses, criteria and phenomena are also frequently misused, often by treating a plural as a singular. Species names such as Saccharomyces cerevisiae and Caenorhabditis elegans cause many errors as well. Most of these become far easier once the word parts inside them are understood.

Is it fluorescence or flourescence?

The correct spelling is fluorescence, beginning with fluor as in fluorine and fluoride. The word was coined in 1852 by the physicist George Gabriel Stokes from the name of the mineral fluorite, which comes from the Latin word for "flow." It has nothing to do with flour. The ending is -escence, with sc, as in adolescence.

Do reviewers care about spelling in scientific papers?

Reviewers judge the science first, and a few typos are unlikely on their own to decide whether a strong paper is accepted. But many reviewers do comment on spelling and language, and some read frequent errors as a sign of careless work. Errors in species names, gene names or chemical names can also cause genuine confusion or make a paper harder to find. A clean manuscript lets the science be judged on its merits.

How do I learn to spell scientific terminology?

Keep a list of the terms you use most, verify each one against an authoritative source, and practice the ones you get wrong by writing them from memory rather than rereading them. Review them again after two days and then after a week, since spaced practice lasts far longer than cramming. Learning the Greek and Latin parts inside terms, such as fluor, centri and sicc, makes many of them easy to rebuild.

Which spelling system should I use for a journal article?

Use the system your target journal specifies in its author guidelines. Some journals use American spelling, some use British spelling, and some use British spelling with -ize endings, known as Oxford spelling. Chemistry journals often follow IUPAC forms such as sulfur. Whichever system applies, use it consistently throughout the paper, including figures, tables and supplementary material.

Is it homogeneous or homogenous?

In scientific writing, homogeneous is the standard spelling for something uniform in composition throughout. Homogenous was once a separate term in biology, and many dictionaries now list it as a variant of homogeneous, but most science editors still expect the longer form. The same applies to heterogeneous. The word breaks down as homo-gene-ous, meaning "of the same kind."

Fix the words you actually get wrong

A few minutes a day, spaced repetition, built only for spelling. Try five words without signing up.