An abbreviation (from Latin brevis, meaning short) is a shortened form of a word or phrase. It consists of a 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.
In strict analysis, abbreviations should not be confused with contractions, acronyms, or initialisms, with which they share some semantic and phonetic functions, though all four are connoted by the term "abbreviation" in loose parlance.[1]:p167An abbreviation is a shortening by any method; a contraction is a reduction of size by the drawing together of the parts. A contraction of a word is made by omitting certain letters or syllables and bringing together the first and last letters or elements; an abbreviation may be made by omitting certain portions from the interior or by cutting off a part. A contraction is an abbreviation, but an abbreviation is not necessarily a contraction. Acronyms and initialisms are regarded as subsets of abbreviations (e.g. by the Council of Science Editors). They are abbreviations that consist of the initial letters or parts of words.
