Part of speech: Adjective (satellite)
with little or no preparation or forethought
Example: his ad-lib comments showed poor judgment; an extemporaneous piano recital; an extemporary lecture; an extempore skit; an impromptu speech; offhand excuses; trying to sound offhanded and reassuring; an off-the-cuff toast; a few unrehearsed comments
Part of speech: Adjective (satellite)
said or done without having been planned or written in advance
Example: he made a few ad-lib remarks
Part of speech: Noun
remark made spontaneously without prior preparation
Example: his ad-libs got him in trouble with the politicians
Part of speech: Adverb
without advance preparation
Example: he spoke ad lib
Part of speech: Verb
perform without preparation
Example: he extemporized a speech at the wedding
Extemporize, Ad-lib, Improvise, Improvize, Extemporise