vast

1 of 2

adjective

: very great in size, amount, degree, intensity, or especially in extent or range
vast knowledge
a vast expanse
vastness noun

vast

2 of 2

noun

: a boundless space
the vast of heavenJohn Milton
Choose the Right Synonym for vast

enormous, immense, huge, vast, gigantic, colossal, mammoth mean exceedingly large.

enormous and immense both suggest an exceeding of all ordinary bounds in size or amount or degree, but enormous often adds an implication of abnormality or monstrousness.

an enormous expense
an immense shopping mall

huge commonly suggests an immensity of bulk or amount.

incurred a huge debt

vast usually suggests immensity of extent.

the vast Russian steppes

gigantic stresses the contrast with the size of others of the same kind.

a gigantic sports stadium

colossal applies especially to a human creation of stupendous or incredible dimensions.

a colossal statue of Lincoln

mammoth suggests both hugeness and ponderousness of bulk.

a mammoth boulder

Examples of vast in a Sentence

Adjective 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
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.
Adjective
The vast majority of cases were in people who were unvaccinated; 27% percent have been in children under the age of 5. Maria Godoy, NPR, 12 Oct. 2025 Flora represents vast acres of farmland in California’s central valley. Kate Wolffe, Sacbee.com, 11 Oct. 2025 The Chinese scientist added that his research also extends to medical imaging, where AI models are trained on vast datasets to identify subtle symptoms such as facial puffiness, swelling, or discoloration that may signal disease. Bojan Stojkovski, Interesting Engineering, 11 Oct. 2025 My grief from witnessing what has been done to my people is so vast, so relentless, that sadness over my grandmother’s death feels like something too indulgent. Reem Kassis, The Atlantic, 11 Oct. 2025 See All Example Sentences for vast

Word History

Etymology

Adjective

borrowed from Latin vāstus or vastus "devoid of habitation, desolate, dreary," also, "of great size, immense," probably in part continuing Indo-European *h1u̯eh2-sto- (whence Old High German wuosti "empty, deserted," Old English wēste, Old Irish fás), in part conflated with another base *wast- of uncertain origin

Noun

noun derivative of vast entry 1, perhaps by analogy with deep entry 1, deep entry 3

First Known Use

Adjective

1585, in the meaning defined above

Noun

1604, in the meaning defined above

Time Traveler
The first known use of vast was in 1585

Browse Nearby Words

Cite this Entry

“Vast.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/vast. Accessed 14 Oct. 2025.

Kids Definition

vast

adjective
ˈvast
: very great in extent, size, amount, degree, or intensity
a vast stretch of desert
vast knowledge
vastly adverb
vastness
ˈvas(t)-nəs
noun

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