Numerous students, even journalists, writers and speakers, trust these words can be exchanged and won’t promptly trust they don’t mean the same, until they read this.

ABBREVIATION (noun)
1. A shortened form of a word or phrase.
(e.g. SKU is the abbreviation for Stock Keeping Unit)

2. The process of abbreviating something.                                                                                             (e.g. Nursing records must be written without abbreviation)

ACRONYM (noun)
An abbreviation formed from the initial letters of other words and pronounced as a word e.g PHCN – Power Holding Company of Nigeria, NATO – North Atlantic Treaty Organization etc. An Acronym is sometimes called initialism. Acronym is a subset of abbreviation. An acronym, technically, must spell out another word. However, this rule isn’t always rigidly enforced. e.g ASAP is an acronym although the word “asap” is not in many dictionaries. Still, the first letters of each of the words “As Soon As Possible” are used to form the acronym ASAP.

Not all abbreviations are Acronyms but all Acronyms are Abbreviations.