Difference between Ad Libitum and Impromptu

AD LIBITUM vs IMPROMPTU: NOUN

Something, such as a speech, that is made or done extemporaneously.
A short composition, especially for the piano, performed in an offhand or extemporized style.
Something said or written, played, etc., at the moment, or without previous study or preparation; an extemporaneous composition or performance.
In music: An extemporized composition; an improvisation.
A composition in irregular form, as if extemporized; a fantasia.
A short musical passage that seems to have been made spontaneously without advance preparation
An extemporaneous speech or remark
Something made or done offhand, at the moment, or without previous study; an extemporaneous composition, address, or remark.
A piece composed or played at first thought; a composition in the style of an extempore piece.
A short musical composition for an informal occasion often with the character of improvisation and usually to be played solo.
Any composition, musical or otherwise, that is created on the spot without preparation.

At the discretion of the performer. Used chiefly as a direction giving license to alter or omit a part.
Of or relating to a diet in which the amount of food is not restricted.

Improvised; without prior preparation; extemporaneous; unplanned.
With little or no preparation or forethought
Prompted by the occasion rather than being planned in advance.
Spoken, performed, done, or composed with little or no preparation; extemporaneous.

Offhand; without previous study or preparation: as, a verse written impromptu.
Prompt; offhand; extempore; extemporized for the occasion: as, an impromptu epigram.

Stoichiometry, Astrocytic, Interconversion, Prandial, Ileal, Overate, Hydroxyproline, Gavage, Ruminal, Equimolar, Keto, Postprandial, Impromptu, Ad lib, Spontaneously

Interim, Unpredictable, Temporary, Hasty, Adlib, Extemporaneous, Makeshift, Spontaneous, Improvised, Informal, Spur of the moment, Ad libitum, Unprepared, Ad lib, Spontaneously

Stoichiometry, Astrocytic, Interconversion, Prandial, Ileal, Overate, Hydroxyproline, Gavage, Ruminal, Equimolar, Keto, Postprandial, Impromptu, Ad lib, Spontaneously

Unforeseeable, Interim, Unpredictable, Temporary, Hasty, Extemporaneous, Makeshift, Spontaneous, Improvised, Informal, Spur of the moment, Ad libitum, Unprepared, Ad lib, Spontaneously

Ability to cope with customers in impromptu situations.
We made an impromptu stop at Dunkin Donuts.
Day Saint Conference Excerpts, plus various impromptu subjects.
Your birthday is like an impromptu beach party.
Professor Stein begins belting out an impromptu musical.
Liverpool after performing his impromptu routines in pubs.
Several companies address their needs for training in an impromptu and indiscriminate way, training in such companies are pretty much impromptu and unsystematic.
Full Text Available Great impromptu speaking, reciting and singing are never just an isolated impromptu act.
Impromptu definition, made or done without previous preparation: an impromptu address to the unexpected crowds.
Impromptu Speeches: Students will be asked to prepare a brief impromptu speech.