To play or frolic (especially of animals or children); to romp or cuddle playfully; also to act playfully or flirtatiously.
猫が毛糸でじゃれている姿がとてもかわいい。
The cat playing with the yarn looks very cute.
子どもたちは庭で水鉄砲を使ってじゃれていた。
The children were playing around with water guns in the yard.
彼は冗談を言って彼女とじゃれていたが、すぐに真面目な話になった。
He was joking and flirting playfully with her, but it soon turned into a serious conversation.