adverb, adverb taking the 'to' particle
Mimics the high-pitched sound of small animals like mice or chicks. Often used adverbially with と.
ネズミがチューチューと鳴いている。
The mouse is squeaking.
adverb, adverb taking the 'to' particle, noun or participle which takes 'suru'
slurp; sucking noisily
Represents the sound of sucking liquid through a straw or similar. Can be used as a suru-verb (チューチューする).
子どもがジュースをチューチュー吸っている。
The child is slurping juice noisily.
noun
Childish word for a mouse, derived from the squeaking sound. Used by or to small children.
ほら、チューチューがいるよ。
Look, there's a mouse!