にたっと

adverb

with a broad grin; smirking

Describes a wide, often unpleasant or knowing grin. Related to にたにた, but にたっと suggests a single, sudden grin.

See also: にたにた

• 彼かれはいたずらを思おもいついて、にたっと笑わらった。

  He thought of a prank and grinned broadly.

• 犯はん人にんはにたっと口くち元もとを歪ゆがめた。

  The criminal twisted his mouth into a smirk.