On the use and misuse of abbreviations in scientific writing

Science should be communicated in clear, coherent, and concise language. Although scientific language is usually simple, that does not mean it is easy to write in a clear, coherent, and concise manner. This letter is written to address one aspect of scientific writing that I have noticed to proliferate in recent years, namely, the use, or, more accurately, the misuse of abbreviations. There is hardly a scientific article I have read recently that does not contain abbreviations. I do not mean well-established abbreviations, like DNA, AI, or USA (abbreviations consisting of the first letters of a word combination are also called initialisms), but abbreviations that have been invented by the authors themselves. Examples of such abbreviations from recent scientific articles are CK, bS, iS, MF, MP, SF, and S. Without reading the articles, it is impossible to know what these abbreviations stand for: CK: control; bS: bulk sulfur; iS: ionic sulfate; MF: macropore flow; MF: mulch film; MP: microplastics; SF: shed film; and S: surface. The problem with invented abbreviations is that anyone can invent an abbreviation, and the same abbreviations can be defined for different words. For instance, the abbreviation PE has been used to mean “polyethylene,” but is also used for “professional engineer,” “physical education,” and many more. Abbreviations may have different meaning in different fields, and we should be cognizant of this fact, particularly as research becomes more inter- and transdisciplinary. Abbreviations should be used sparingly. Although abbreviations make the writing more concise, they also make the writing less clear, because a reader may not remember what an abbreviation means, particularly when excessive numbers of abbreviations are used. Abbreviation should be used to shorten long words or word combinations that are used repeatedly in an article. Short words should not be abbreviated. And, abbreviations should, at the very least, consist of letter that actually occur in the word that is abbreviated. The most amazing abbreviation I have seen is “CK” for the word “control.” First, the word “control” is so short that no abbreviation is warranted; and second, there is no letter “K” in the word “control.” The use of “CK” is so common in published scientific articles that I wonder whether authors using this abbreviation have ever wondered about why they are using it and whether it makes sense. Maybe because they have seen this abbreviation in a previously published article, and have just copied what others have written before? And I further wonder why reviewers and editors are not objecting to the use of such unreasonable abbreviations. Abbreviations are also often used in figures and tables, even when there is sufficient space in a figure or a table to spell out the words that are abbreviated. Again, this makes the reading and comprehension of a figure or table unnecessarily cumbersome and difficult. If there is space available in a figure or a table, spell out the abbreviations; this helps the reader as well as the authors to understand figures and tables more easily. Rules for proper use in scientific writing include that they should be defined at their first use, except if it is a common abbreviation that can be found in standardized lists of abbreviations. Such lists can be found in style manuals (e.g., ASA, CSSA, SSSA, 2024; Chicago Manual of Style, 2024; Coghill & Garson, 2006), which should be consulted and followed when writing for respective audiences. Abbreviations should be avoided in titles, and abbreviations should be used sparingly and only if the words occur frequently. Abbreviations have their role in scientific writing, they can make the writing more concise and can contribute to clarity. For instance, it makes sense to abbreviate “time-domain reflectometry” to “TDR” or “Fourier-transformed infrared spectroscopy” to “FTIR.” But excessive use of abbreviations, particularly newly invented ones, compromises clarity and understanding, the prime pillars of good scientific writing. When I write a scientific article, I always ask myself whether an abbreviation is really necessary, and I try to avoid them as much as possible. Markus Flury: Conceptualization; writing–original draft.