interjection
Casual interjection used by young people, often when drinking together or as a light greeting among friends. Similar to 'hey' or 'cheers' in English.
「ウェーイ!」と言って乾杯した。
They toasted, saying 'Cheers!'
友達に会ったら「うぇーい」って挨拶する。
When I meet my friends, I greet them with a 'Hey!'