Abridgment

First attested in 1494. From Middle English abrygement,

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from Middle French abrÃ©gement.

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Equivalent to abridge + -ment.

Full definition of abridgment

(plural abridgments)

(US) The act of abridging, or the state of being abridged; diminution; lessening; reduction or deprivation; as, an abridgment of pleasures or of expenses. First attested from around (1350 to 1470).
(US) An epitome or compend, as of a book; a shortened or abridged form; an abbreviation. First attested from around (1350 to 1470).

22 March 2012, Scott Tobias, AV Club The Hunger Gameshttp://www.avclub.com/articles/the-hunger-games,71293/When the goal is simply to be as faithful as possible to the materialâ€”as if a movie were a marriage, and a rights contract the vowâ€”the best result is a skillful abridgment, one that hits all the important marks without losing anything egregious.

(obsolete) That which abridges or cuts short; hence, an entertainment that makes the time pass quickly

What abridgment have you for this evening? What masque? what music? - Shakespeare, Midsummer Night's Dream, V-i

(dated, legal) Any of various brief statements of case law made before modern reporting of legal cases.

In current usage this spelling is about as common as abridgement in the US, but much less common in the UK.

Notes on near-synonyms:

An abridgment is made by omitting the less important parts of some larger work; as, an abridgment of a dictionary.

A compendium is a brief exhibition of a subject, or science, for common use; as, a compendium of American literature.

An epitome corresponds to a compendium, and gives briefly the most material points of a subject; as, an epitome of history.

An abstract is a brief statement of a thing in its main points.

A synopsis is a bird's-eye view of a subject, or work, in its several parts.