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にやつく Japanese meaning | Kotomora

にやつく

Meanings

1

godan verb (-ku)

smirk; grin broadly

Describes a self-satisfied, knowing, or sly smile, often with a hint of amusement or smugness. Related to にやにや, which is the adverbial form.

See also: にやにや

彼かれは何なにか企たくらんでいるようににやついた。
He smirked as if he was plotting something.
褒ほめ

られ

て

、

つい

にやつい

て

しまっ

た

。

Being praised, I couldn't help but grin broadly.

Written forms

にやつくUsage45%
Hiragana spelling is standard; the katakana form ニヤつく is also used for emphasis or in informal writing.
ニヤつくUsage55%
Katakana variant often seen in manga or casual contexts to emphasize the smirk.

Similar words

にやにや
にやにや is an adverb describing the state of smirking continuously, while にやつく is a verb meaning to break into or show a smirk.
ほくそ笑えむ
ほくそ笑む implies a more secretive, inward chuckle of satisfaction, often at someone else's misfortune, whereas にやつく is a visible smirk.

Etymology

Derived from the mimetic adverb にやにや (smirkingly) combined with the verb-forming suffix つく. The exact origin of にや is uncertain, but it is likely sound-symbolic for a sly smile.