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Definitions

flat out

[flat-out] / ˈflætˈaʊt /
ADVERB
at top speed
Synonyms
WEAK
all out at full speed at full throttle bluntly directly full-bore openly peak performance wide open
flat-out
ADVERB
at top speed
Synonyms
WEAK
all the way all-out at a good clip for all one's worth full blast head over heels in full gallop lickety-split the whole nine yards to the max unrestrainedly wide open without reservation

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

F1 bosses are due to meet in the four-week gap between Japan and the next race in Miami to discuss changes to the rules to allow drivers to push flat-out in qualifying.

From BBC • Mar. 29, 2026

His accusation, Jones told Salon, is flat-out false.

From Salon • Mar. 11, 2026

So Sauer’s claim that Murphy forced an unscheduled emergency stopover in Djibouti is just flat-out false.

From Slate • Feb. 28, 2026

Poor Sofia Coppola, a last-minute replacement for Winona Ryder, flat-out couldn’t act.

From Los Angeles Times • Feb. 17, 2026

One night, when we had turned the lights off, he flat-out asked what I was doing in the Academy.

From "Newjack: Guarding Sing Sing" by Ted Conover