ad lib

¹ American  

[ad lib, ad] / æd ˈlɪb, ˈæd /

noun

1. something improvised in speech, music, etc..

   Was that joke part of your speech or an ad lib?

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adverb

1. at one's pleasure; without restriction.

2. freely; as needed; without stint.

   Water can be given to the patients ad lib.

ad lib. ² American  

abbreviation

1. ad libitum.

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ad-lib ³ American  

[ad-lib, ad-] / ædˈlɪb, ˈæd- /

verb (used with object)

ad-libbed, ad-libbing

1. to improvise all or part of (a speech, a piece of music, etc.).

   to ad-lib one's lines.

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verb (used without object)

ad-libbed, ad-libbing

1. to act, speak, etc., without preparation.

   Throughout the play he had to ad-lib constantly.

adjective

1. impromptu; extemporaneous.

   ad-lib remarks to hecklers.

ad-lib British  

/ ædˈlɪb /

verb

1. to improvise and deliver without preparation (a speech, musical performance, etc)

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adjective

1. improvised; impromptu

adverb

1. without restraint; freely

2. music short for ad libitum

noun

1. an improvised performance, often humorous

Other Word Forms

• ad-libber noun

Etymology

Origin of ad lib¹

First recorded in 1810–20; ad libitum

Origin of ad-lib³

1915–20, v. use of ad lib

Example Sentences

I could ad lib those two scenes with the boys when I wake them up.

From Los Angeles Times • Jan. 29, 2024

"I've realised that usually I like to ad lib but you can't ad lib a script because your fellow actor doesn't know when you're going to stop talking."

From BBC • Apr. 13, 2023

Sure enough, after three months, the mice who ate ad lib were stricken with obesity, diabetes, liver disease, and a host of other ugly conditions.

From Salon • Oct. 9, 2022

There are conflicting stories about when the ad lib started.

From Seattle Times • Jan. 19, 2021

So the next day I go to Room 402 at lunch and do my best to volley back right answers to Rosa’s ad lib math problems.

From "The Running Dream" by Wendelin Van Draanen