Traditional brackets
The standard way to introduce an acronym or initialism is to place it in round brackets after the full term. This is the approach I’ve used in many of the above examples. That is, suppose we wish to introduce the initials ‘AWP’ for ‘acoustic wave propagator’. We would write:
Correct: “In this paper, an acoustic wave propagator (AWP) approach is employed to investigate sound propagation around a barrier.”
This approach is the simplest and the easiest to understand and follow, so it is the most commonly used in academic writing. This is therefore the default approach for most writers.
However, there are several other ways to introduce an acronym or initialism, each with its own benefits. I mentioned earlier that many editors and journals will automatically call for acronyms and initialisms to be introduced at the first use of a term in a body of text, but I also discussed the benefits of introducing them later or reintroducing them at different points. These alternative approaches for explaining an acronym are useful for allowing a writer to reintroduce acronyms and initialisms or to introduce them later in a document.
Explicit introduction
The most obvious way to introduce an acronym or initialism is to explicitly introduce it within the sentence. That is, rather than simply putting the initials in brackets, the sentence explicitly presents them as an alternative name. Let’s look at some examples:
- Correct: “They developed the acoustic wave propagator, also known as an AWP, as an analogy to the quantum wave propagator.”
- Correct: “They developed the acoustic wave propagator, or AWP, as an analogy to the quantum wave propagator.”
- Correct: “They developed the acoustic wave propagator, abbreviated as AWP, as an analogy to the quantum wave propagator.”
- Correct: “They developed the acoustic wave propagator, written as AWP, as an analogy to the quantum wave propagator.”
- Correct: “They developed the acoustic wave propagator (hereafter, AWP) as an analogy to the quantum wave propagator.”
This approach emphasizes the use of ‘AWP’ as an abbreviation for acoustic wave propagator. This is a good way to preserve a late or repeated introduction so that an editor won’t shift it. For example, let’s look at the formal definition of the acoustic wave propagator:
Correct: “Integrating Equation 3.8 with respect to time produces a formal solution for the state vector Φ(x, t), where exp(−(t−t0)H) is the acoustic wave propagator, or AWP.”
This way, we can reintroduce or late-introduce the initials AWP and explain to the reader that this is a propagator function for the acoustic wave equation, while also using the full name as part of the formal definition.
This approach is also useful for stressing that a particular acronym or initialism is an alternate standard or common name, not merely an abbreviation. For example:
- Correct: “Schemes for quantum computation are based around interactions between external control fields and quantum bits, or qubits for short.”
- Correct: “Using data from the Wilkinson Microwave Anisotropy Probe, also known simply as WMAP, we analyze the cosmic microwave background (CMB).”
Reversed explanation
Another way to introduce an acronym or initialism is a reverse approach, that is, to give the initials first followed by the full name. Let’s see how that would look:
- Correct: “The algorithms were coded in the Fortran 90 programming language using the FFTW (Fastest Fourier Transform in the West) package.”
This approach emphasizes the initials over the full name. This is useful for cases where the acronym or initialism is the proper name, and the full term is more of a description, as is the case with many software titles, project names, and things named with backronyms and contrived acronyms, which might be too difficult to explain in the normal way. Let’s look at some more examples:
- Correct: “Integrating Equation 3.8 with respect to time produces a formal solution for the state vector Φ(x, t), where exp(−(t−t0)H) is the AWP, that is, an acoustic wave propagator.”
- Correct: “The Navier–Stokes equations are solved using the SIMPLEC algorithm (Semi-Implicit Method for Pressure Linked Equations-Consistent).”
- Correct: “Schemes for quantum computation are based around interactions between external control fields and qubits, or quantum bits.”
- Correct: “We employ a hydrogen maser (for ‘microwave amplification by stimulated emission of radiation’) as a frequency reference…”
By reversing the standard rule and added extra emphasis, this approach can be used to preserve a repeated introduction being used as a reminder for the reader, as an editor ought to think twice before removing it.
Capitalized letters
You will often see acronyms and initialisms introduced with the initial letters of the full term capitalized. For example:
Correct but unclear: “In this paper, an Acoustic Wave Propagator (AWP) approach is employed to investigate sound propagation around a barrier.”
This emphasizes which letters are used in the acronym or initialism; here, A, W, and P are capitalized and so make up ‘AWP’. This is particularly useful when the acronym or initialism is made up of letters that aren’t necessarily the initial letters. For example,
- Correct but unclear: “Quantum ChromoDynamics (QCD)”
- Correct but unclear: “Superconducting QUantum Interference Device (SQUID)”
- Correct but unclear: “FLoridA Multi-object Imaging Near-infrared Grism Observational Spectrometer (FLAMINGOS)”
However, although this is a common style, I don’t believe this is an effective approach, as it can be ambiguous or confusing to a reader. In written English, capital letters are reserved for the beginnings of sentences, titles, and proper nouns, that is, the names of people, organizations, and commercial products. Using capital letters for ordinary terms makes them appear to be proper nouns, not common nouns, which can be confusing for the reader. For example, ‘Acoustic Wave Propagator’ appears to be the official name of a software program or algorithm, which is incorrect; ‘acoustic wave propagator’ is an ordinary noun for a mathematical function. In addition, the extra capital letters in words like ‘QUantum’ and ‘FLoridA’ make them harder to read and they don’t appear like normal words or names. Instead, I feel most readers are familiar with acronyms and initialisms enough to know that the first letters of each word will make up the following acronym or initialism, if it is simple: “acoustic wave propagator (AWP)” is quite clear. I recommend reserving capital-letter introductions for proper nouns and for complex acronyms and initialisms in reversed introductions. For example:
- Proper noun with capitals: “…at the National Center for Research on Earthquake Engineering (NCREE).”
- Proper noun with capitals: “…using the Semi-Implicit Method for Pressure Linked Equations-Consistent (SIMPLEC) algorithm.”
- Proper noun with capitals and reverse introduction: “…using the SIMPLEC (Semi-Implicit Method for Pressure Linked Equations-Consistent) algorithm.”
- Proper noun with capitals and reverse introduction: “with the FLAMINGOS (FLoridA Multi-object Imaging Near-infrared Grism Observational Spectrometer)”
- Common noun with reverse introduction: “using a SQUID (Superconducting QUantum Interference Device) to measure…”
Nevertheless, you should check the author guidelines for a journal or conference to see if they have a preferred style before submitting your paper.