[ ad -lib, ad ]
/ æd ˈlɪb, ˈæd /
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something improvised in speech, music, etc.: Was that joke part of your speech or an ad lib?
at one's pleasure; without restriction.
freely; as needed; without stint: Water can be given to the patients ad lib.
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On the farm, the feed for chicks is significantly different from the roosters’; ______ not even comparable.
Origin of ad lib
First recorded in 1810–20; see origin at ad libitum
Definition for ad lib (2 of 3)
[ ad-lib, ad- ]
/ ædˈlɪb, ˈæd- /
verb (used with object), ad-libbed, ad-lib·bing.
to improvise all or part of (a speech, a piece of music, etc.): to ad-lib one's lines.
verb (used without object), ad-libbed, ad-lib·bing.
to act, speak, etc., without preparation: Throughout the play he had to ad-lib constantly.
impromptu; extemporaneous: ad-lib remarks to hecklers.
Origin of ad-lib
1915–20, Americanism; v. use of ad lib
OTHER WORDS FROM ad-libad-libber, noun
Definition for ad lib (3 of 3)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
British Dictionary definitions for ad lib
/ (ædˈlɪb) /
verb -libs, -libbing or -libbed
to improvise and deliver without preparation (a speech, musical performance, etc)
adjective (ad lib when predicative)
adverb ad lib
without restraint; freely
music short for ad libitum
an improvised performance, often humorous
Derived forms of ad-libad-libber, noun
Word Origin for ad-lib
C18: short for Latin ad libitum, literally: according to pleasure
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medical definitions for ad lib
ad libitum (freely, as desired)
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.