The ACS Style Guide has always been a classic handbook for scientific publication. But in 2020, it was revised and expanded as the ACS Guide to Scholarly Communication. The ACS Guide to Scholarly Communication not only provides students, researchers, educators, and librarians with professional guidance, it also helps researchers at different stages of their careers to respond to the […]

The words chosen by a writer are one of the defining characteristics of that author’s style; however, word choice is not governed by style alone. The audience for an article must influence a writer’s choice of words so that the writer can select words that are likely to be known to the audience and define the words that are not. The type of document also may influence a writer’s word choices because some documents, such as journal articles and books, tend to require more formal word usage, whereas other documents, such as emails, allow less formality.

Common Confusing Words and Phrases

The choice of the correct word to express meaning begins with a good dictionary, but it also extends to understanding small differences in meaning between two words or phrases that are almost synonymous or that are spelled similarly but have significant differences in meaning. It is best to use words in their primary meanings and to avoid using a word to express a thought if such usage is uncommon, informal, or primarily literary. Many words are clear when you are speaking because you can amplify your meaning with gestures, expressions, and vocal inflections, but when these same words are written, they may be clear only to you.

Words: Assure vs. Ensure vs. Insure

Usage: To assure is to affirm; to ensure is to make certain; to insure is to indemnify for money.

Example sentences:

He assured me that the work had been completed.

The procedure ensures that clear guidelines have been established.

You cannot get a mortgage unless you insure your home.

Phrases: Based on vs. On the basis of

Usage: Phrases starting with “based on” must modify a noun or pronoun that usually immediately precedes or follows the phrase. Use phrases starting with “on the basis of” to modify a verb.

Example sentences:

The doctors’ new methods in brain surgery were based on Ben Carson’s work.

On the basis of the molecular orbital calculations, we propose a mechanism that can account for all the major features of alkali- and alkaline-earth-catalyzed gasification reactions. (not ‘based on’)

Words: Comprise vs. Compose

Usage: Use “to comprise” to mean “to contain” or “to consist of”; it is not a synonym for “to compose.” The whole comprises the parts, or the whole is composed of the parts, but the whole is not “comprised of” the parts. Never use “is comprised of.”

Example sentences:

INCORRECT: A book is comprised of chapters.

CORRECT: A book comprises chapters.

CORRECT: A book is composed of chapters.

Using Gender-Neutral Languages

Most publishers have gone to great effort to eliminate the use of gender-biased language from their publications. Gender-neutral language is also now expected in scientific publishing. Current style guides and writing guides urge copy editors and writers to choose terms that do not reinforce outdated sex and gender roles.

Gender-neutral language can be accurate and unbiased and not necessarily awkward. The most problematic words are the noun “man,” when used to refer to humans generally, and the pronouns “he” and “his,” when used to refer to a nonspecific individual. These terms are no longer considered gender-neutral, but there are usually several satisfactory gender-neutral alternatives for these words. Choose an alternative carefully and keep it consistent with the context. Of course, if the identity of the person being discussed is known, then it is perfectly acceptable to use their specified pronouns.

How to Use a Comparative Phrase

Words: Fewer vs. Less

Usage: Use “fewer” to refer to number; use “less” to refer to quantity. However, use “less” with number and unit of measure combinations because they are regarded as singular.


Fewer than 50 animals

Fewer than 100 samples

Less product

Less time

Less work

Less than 5 mg

Less than 3 days

Phrases: Greater than vs. More than vs. Over vs. In excess of

Usage: Use the more accurate terms “greater than” or “more than” rather than the imprecise “over” or “in excess of.”

Example sentences:

Greater than 50% (not in excess of 50%)

More than 100 samples (not over 100 samples)

More than 25 mg (not in excess of 25 mg, not over 25 mg)

Phrases: On (the) one hand and On the other hand

Usage: Use “on (the) one hand” and “on the other hand” to present conflicting points of view. These two phrases should be used only as a pair, never alone, and preferably within a few sentences of each other. In other words, use “on the other hand” only if “on (the) one hand” precedes it.

Example sentences:

On (the) one hand, we wanted to arrive early so that we could practice our presentation and correct any last-minute problems. On the other hand, we did not want to miss the current session of talks and the opportunity to talk to others about their research.

Avoid Using Inappropriate Words and Expressions

Write in a style that conveys the intended meaning using simple, subject-appropriate language. Avoid slang and jargon, which are expressions in the common vernacular that are not formal enough to be appropriate in a professional context. Write as if speaking to a colleague. For instance, instead of writing, “We put the sample in the fridge for a while,” write, “We stored the sample in the refrigerator at 4 ºC overnight.”

Do not use “respectively” when you mean “separately” or “independently.”

INCORRECT: The electrochemical oxidations of chromium and tungsten tricarbonyl complexes, respectively, were studied.

CORRECT: The electrochemical oxidations of chromium and tungsten tricarbonyl complexes were studied separately.

Avoid using contractions and abbreviations:


CORRECT: Was not

INCORRECT: In the lab

CORRECT: In the laboratory

Avoid using such redundant sentence structures as “it is,” “there are,” and “this is”:

INCORRECT: It is a procedure that is often used.

CORRECT: This procedure is often used.

INCORRECT: There are seven steps that must be completed.

CORRECT: Seven steps must be completed.

INCORRECT: This is a problem that is prevalent in the sciences.

CORRECT: This problem is prevalent in the sciences.

For more information on using making better word choices, please refer to section 5.1.1 of the ACS Guide to Scholarly Communication.

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