Simple Definition of vast
: very great in size, amount, or extent
Full Definition of vast
: very great in size, amount, degree, intensity, or especially in extent or range <vast knowledge> <a vast expanse>
Examples of vast
She has a vast amount of knowledge on this subject.
The policy is supported by the vast majority of citizens.
a vast expanse of land
Origin of vast
Latin vastus; akin to Old High German wuosti empty, desolate, Old Irish fás
First Known Use: 1585
Synonym Discussion of vast
Definition of vast
: a boundless space <the vast of heaven — John Milton>
First Known Use of vast
Seen and Heard
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