Pronunciation: (ad lib', ad'),[key] 1. something improvised in speech, music, etc.: Was that joke part of your speech or an ad lib? 2. at one's pleasure; without restriction.
3. freely; as needed; without stint: Water can be given to the patients ad lib.
Pronunciation: (ad lib', ad'-),[key] —v.,-libbed, -lib•bing, —adj.
—v.t. to improvise all or part of (a speech, a piece of music, etc.): to ad-lib one's lines.
—v.i. to act, speak, etc., without preparation: Throughout the play he had to ad-lib constantly.
—adj. impromptu; extemporaneous: ad-lib remarks to hecklers.