vastly

adverb

vast·​ly ˈvast-lē 

: to a very great or vast degree or extent : exceedingly

two people with vastly different tastes

a vastly more powerful bomb

But bluff and bravado … won against potential enemies who vastly outnumbered him.

—David Gilmour

It was the most eclectic—yet also vastly entertaining—evening of dance I have seen in a long time.

—Rita Felciano

Synonyms of vastly

• extremely
• incredibly
• very
• highly
• terribly
• too
• greatly
• severely
• badly
• so
• far
• damned
• wildly
• damn
• really
• desperately
• heavily
• much
• seriously
• intensely
• immensely

Examples of vastly in a Sentence

the team has vastly improved in the course of the season

vastly underestimated the cost of advertising the new product

Recent Examples on the Web

But though basketball and baseball are vastly different games, the Warriors might be able to execute some variation of that tactic on the court. —Joseph Dycus, Mercury News, 23 Jan. 2026

But while the Russian military vastly outmans and outguns the Ukrainians, Moscow has so far failed to seize the region in its entirety. —Ivana Kottasová, CNN Money, 23 Jan. 2026

If Levin is right that intelligent behavior can emerge from simple algorithms, what might be emerging in AI systems, which are vastly more complex? —Tharin Pillay, Time, 22 Jan. 2026

Doing so would make way for a faster, safer and vastly cheaper alternative, while allowing the agency to refocus on R&D and space science. —Editorial, Boston Herald, 21 Jan. 2026

Word History

First Known Use

1598, in the meaning defined above

Rhymes for vastly

• ghastly
• lastly
• steadfastly