Adverb (fukushi), Suru verb
making out; necking; getting handsy; canoodling; being lovey-dovey; getting affectionate (with each other); romantic play; fondling
Onomatopoeic or mimetic word
街中でイチャイチャするカップル見たら腹立ちませんか？Doesn't it irritate you to see couples making out around town?
Also written いちゃいちゃ