xī​xī

happy

嘻嘻 xī​xī
happy descriptive
expressing joy, merriment, or a cheerful state

He's giggling all day and seems to have no worries at all.

hee hee descriptive
onomatopoeia representing the sound of giggling or chuckling

Looking at that funny photo, she couldn't help giggling.

Frequency

Written text
22.7 per million

Sources

Definitions
CC-CEDICT
Frequency data
BCC Corpus (BLCU)