ad libitum

American  

[ad lib-i-tuhm, ahd lib-i-toom] / æd ˈlɪb ɪ təm, ɑd ˈlɪb ɪˌtʊm /

adjective

1. at one's pleasure.

2. Music. not obligatory or indispensable. ad lib.

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ad libitum British  

/ ˈlɪbɪtʊm, -təm /

adjective

1. Often shortened to: ad lib.  music (to be performed) at the performer's discretion

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Etymology

Origin of ad libitum

Borrowed into English from Latin around 1695–1705

Example Sentences

In the experiment, the mice on the ad libitum schedule gained weight and experienced metabolic dysfunction, whereas the mice on time restricted feeding did not.

From Salon • Jan. 25, 2023

Half of the mice ate all their food in 8 hours during the night, as mice usually do, while the other half ate ad libitum, anytime they wanted.

From Salon • Oct. 9, 2022

This form of husbandry, known as ad libitum feeding, is cheap and convenient since animal technicians need only check the hoppers from time to time to make sure they haven’t run dry.

From Slate • Nov. 16, 2011

It is independent ; 'one can rise at any hour one pleases,' fix one's own office hours, take days off ad libitum.

From Time Magazine Archive

The Patriarch rises very early, and says prayers at dawn, after which those who have the entrée are served with pipes and coffee in his room, and talk ad libitum.

From Journeys in Persia and Kurdistan, Volume II (of 2) Including a Summer in the Upper Karun Region and a Visit to the Nestorian Rayahs by Bird, Isabella L. (Isabella Lucy)