Flat-out

Synonyms for "flat-out" (82 found)

Ranked by relevance and common usage.

Closest matches (17)

absolute all out apace arrant categorical clear complete conclusive decided decisive definite definitive

Adverb(5 words)

absolutely all ends up altogether categorically completely

Strong matches (24)

determinate downright entire expeditiously explicit express fast final fixed flat flat out full tilt global hastily implicit indisputable out-and-out

Adverb(6 words)

downright finally first and last handsomely lock, stock and barrel nothing but

Adjective(1 words)

Related words (41)

Sample sentences

6 total sentences available.

Tatoeba + Wiktionary

He flat-out lied.

Source: tatoeba (2431982)

Mary is flat-out gorgeous.

Source: tatoeba (6866150)

That's a flat-out lie.

Source: tatoeba (9009578)

That was a flat-out lie.

Source: tatoeba (11500284)

Showing 4 of 6 available sentences.

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Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.