[ flat-out ]
See synonyms for flat-out on Thesaurus.com
  1. moving or working at top speed or with maximum effort; all-out: a flat-out effort by all contestants.

  2. downright; thoroughgoing: Many of the paintings were flat-out forgeries.

Origin of flat-out

First recorded in 1925–30

Words Nearby flat-out

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use flat-out in a sentence

  • It was all like putting a man in a racing car traveling flat out on the Salts in Bonneville, Utah.

    What Need of Man? | Harold Calin
  • It was no use, however, it is next to impossible to throw a man when he is lying flat out as the Brahmin now was.

  • And now lay down that purse,” he continued briefly, “before I shoot the flat out of your eye.

    Silver and Gold | Dane Coolidge
  • Pigeons were cooing near, and several dogs were lying flat out in the shade which the wide eaves of the house afforded.

    Polly | L. T. Meade
  • He has the term to finish, and certainly you would not have him flat out on his job when the end is in sight.

    The Story of Porcelain | Sara Ware Bassett

Other Idioms and Phrases with flat-out


In a direct manner, bluntly. For example, He told the true story flat out. [Colloquial; mid-1900s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.