ニマニマ

adverb, adverb taking the 'to' particle, noun or participle which takes 'suru'

smiling; grinning

Describes a quiet, self-satisfied smile, often with a hint of creepiness or slyness. Often used with と and する.

See also: ニヤニヤ

• 彼かれは一人ひとりでニマニマと笑わらっていた。

  He was grinning to himself.