ad-libbed; ad-libbing

transitive verb

: to deliver spontaneously

intransitive verb

: to improvise especially lines or a speech
ad-lib noun

ad-lib

2 of 3

adjective

: spoken, composed, or performed without preparation

ad lib

3 of 3

adverb

1
: in accordance with one's wishes
2
: without restraint or limit

Examples of ad-lib in a Sentence

Verb had to ad-lib constructing a piñata because she'd never actually seen it being done Adjective not bad for an ad-lib comedy routine
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Verb
Being able to ad-lib was such a steep learning curve for me. Patrick Saunders, Denver Post, 6 Apr. 2025

Word History

Etymology

Verb

derivative of ad lib

Adjective

derivative of ad lib

Adverb

short for ad libitum entry 1

First Known Use

Verb

1910, in the meaning defined at transitive sense

Adjective

1819, in the meaning defined above

Adverb

1791, in the meaning defined at sense 1

Time Traveler
The first known use of ad-lib was in 1791

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Cite this Entry

“Ad-lib.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ad-lib. Accessed 14 Jun. 2025.

Kids Definition

ad-lib

1 of 3 verb
(ˈ)ad-ˈlib
ad-libbed; ad-libbing
: to improvise especially lines or a speech

ad-lib

2 of 3 adjective
: spoken, composed, or performed without preparation
an ad-lib speech

ad lib

3 of 3 adverb
: without restraint or limit
known for talking ad lib

Medical Definition

: made or done spontaneously : not controlled by a schedule
ad-lib feeding of animals
: without restraint or imposed limit : as much or as often as is wanted
the animals were given water ad lib Science
often used in writing prescriptions

More from Merriam-Webster on ad-lib

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