Brag, boast, as in I don't believe he's ever shot even a duck, but he sure talks big about hunting. This colloquial idiom was first recorded in 1699.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
How to use talk big in a sentence
But ma she tells him 't a man 't never does anything else might as well talk big words as little ones.Dorothy at Skyrie | Evelyn Raymond
My wife is still in the hills, and we can talk big game without fear of boring the other sex.The Tigress | Anne Warner
You're like all the rest of them: you talk big, but you really don't want anything very important.Twelve Men | Theodore Dreiser
You think me a grand gentleman, because I talk big, and am full of noble sentiment.Sketches in Lavender, Blue and Green | Jerome K. Jerome
The constable and his mate talk big, a crowd gathers round, and 'A ring!Australian Heroes and Adventurers | William Pyke