godan verb (-gu), intransitive verb
frolic; make merry; be in high spirits
Describes lively, cheerful, often noisy behavior, especially of children or people in a festive mood. Can imply being carried away with excitement.
子供たちが公園ではしゃいでいる。
The children are frolicking in the park.
彼はパーティーで少しはしゃぎすぎた。
He got a little too carried away at the party.