Abbreviation. An abbreviation is a shortened form of a word or phrase. Usually, but not always, it consists of a letter or group of letters taken from the word or phrase.For example, the word abbreviation can itself be represented by the abbreviation abbr., abbrv. or abbrev. contraction is an abbreviation, but an abbreviation is not necessarily a contraction. However, normally, acronyms are regarded as a subgroup of abbreviations. Abbreviations can also be used to give a different context to the word itself, such as PIN Number.