To summarize, let’s look at some examples where acronyms and initialisms might not need to be defined:
- “We construct a 3D model of the building…” – It will be understood that this is three-dimensional model.
- “The algorithm was run on a computer with a 2.4 GHz CPU…” – It’s well known that a CPU (meaning ‘central processing unit’) is a computer component and this is clear from the context.
- “The map data uses a 2D CAD file format (AutoCAD)…” – AutoCAD is the name of the software, and doesn’t require further explanation. Depending on the field, it might not be necessary to explain ‘computer-aided design’ (CAD) here.
- “We added 27 g of NIPAM (Acros Organics, USA) to the aqueous solution.” – The name NIPAM is sufficient to identify the chemical N-isopropyl acrylamide. USA is a well-known country, and its full name isn’t very important here, only the name of the company that produced the chemical.
- “To replace silicon in CMOS digital logic circuits, materials require a band gap above 400 meV.” – The complementary metal–oxide–semiconductor (CMOS) is well known in the field of integrated circuits, so this long, complex term is avoided.
But how do you know if a particular acronym or initialism is well known to the readers? How do you know if it is common in the language or in the field of research? A native speaker might know it well, but someone who is less familiar with the language and all its vocabulary might not know it at all. An expert in the field might be very familiar with a term and its abbreviation, but a student just beginning to study the field might still be unfamiliar. If you’re not sure if an acronym or initialism would be well known to the average reader or to an expert in the field, I recommend always explaining the meaning to make it completely clear what you mean. After all, many kinds of people might read the paper: people unfamiliar with English, students just entering the field, researchers from other fields, reporters, and curious members of the public. We editors also come from other fields, and we’ll always ask if acronym or initialism needs to be explained to the reader. If in doubt, write it out! In summary, let’s list the various reasons for not explaining an acronym or initialism:
| Reason | Situation | Example | Omitted explanation |
|---|---|---|---|
| It’s become a proper word. | It never needs to be explained, unless vital for discussion. | scuba | self-contained underwater breathing apparatus |
| It’s well known in everyday speech. | It is explained when necessary for clarity or to avoid ambiguity. | DVD | digital versatile disc or digital video disc |
| It’s well known in the field. | It does not need to be explained when a journal provides a list of accepted abbreviations and it is on the list. It sometimes does not need to be explained if it is thought to be very familiar to the reader. | NMR in The Journal of Biological Chemistry | Nuclear magnetic resonance, in both article title and article text |
| The full name is very long or difficult. | If not necessary for understanding, it might not need to be explained, if the reader can work it out separately. | AMPA | α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid |
| It’s the name of a company or well-known country. | It rarely needs to be explained, unless necessary for clarity | JASCO | Japan Spectroscopic Corporation |
| It’s the name of a program, device, or project. | It sometimes needs to be explained, when necessary for explanation of what it involves. | SIMPLER | SIMPLE Revised |