くすくす

く

す

く

す

JLPTN1Freq.FrequencyTop 50,000

Meanings

1

Describes a quiet, suppressed laugh, often shared among a small group or when trying not to be heard. Frequently used with 笑う.

友とも達だちとくすくす笑わらいながら話はなした。

I chatted with my friend while giggling quietly.

教きょう室しつの後うしろで誰だれかがくすくす笑わらっている。

Someone is chuckling in the back of the classroom.

ゲラゲラN1
げらげら describes loud, unrestrained laughter, while くすくす describes quiet, suppressed giggling.
うふふ
うふふ is itself the sound of a single coy giggle, while くすくす is an adverbial mimetic word describing repeated stifled laughter.

ニコニコN3
にこにこ describes a silent smiling expression, whereas くすくす specifically includes the sound of stifled laughter.
にやにやN3
くすくす describes a quiet, audible giggle, while にやにや describes a silent grin or smirk without laughter.

Onomatopoeic word mimicking the sound of a suppressed laugh.