Pluralizing abbreviations—A classic case of unnecessarily complicating simple matters

If the word takes an 's' in the plural, so does its abbreviation.

• Electrocardiogram - ECG (Singular)

• Electrocardiograms - ECGs (Plural)

If the word does not take an 's' in the plural, its abbreviation also does not.

• Reactive oxygen species - ROS (Singular)

• Reactive oxygen species - ROS (Plural)

Tricky ones—Abbreviations for words that have irregular plurals will also take an 's'

Respiratory syncytial virus - RSV (Singular)

Respiratory syncytial viruses - RSVs (Plural)

Suprachiasmatic Nucleus - SCN (Singular)

Suprachiasmatic Nuclei - SCNs (Plural)

IMPORTANT

If a word is to be applied in the plural form in a sentence, its abbreviated form should be plural, not singular.

Adrenergic receptors (ARs) are present throughout the nervous system.

• AR are important for neurotransmission (wrong)

• ARs are important for neurotransmission (correct)