The second (party, rank, etc.); B (grade); the latter — used as the counterpart to 甲.
書類は甲・乙・丙の順に分類されている。
The documents are classified in the order甲, 乙, 丙.
商談の相手は甲ではなく乙の会社だった。
The business counterpart was the company labeled '乙', not '甲'.
Stylish; chic; tasteful; witty — a colloquial/old-fashioned adjectival sense (pronounced おつ).
彼の着物の柄は乙だね。
The pattern of his kimono is very stylish.
あの店の内装はちょっと乙な雰囲気がある。
That shop's interior has a somewhat chic/unique atmosphere.
Quaint; odd; having a quaint charm — often has an archaic or literary nuance (pronounced おつ).
古い旅館の佇まいが乙でとても落ち着く。
The appearance of the old inn is quaint and very calming.
彼女の言い回しは少し乙なところがある。
Her way of speaking has a slightly quaint/unique quality.
Slang/abbreviation of 'otsukaresama' meaning 'thanks' or 'good job' (used online or in casual speech).
対戦お疲れ！乙！
Good game! Otsu (well done)!
会議終わりにチャットで『乙』とだけ書かれていた。
After the meeting, someone only wrote '乙' in the chat.
Used colloquially/slangily as a short farewell (like 'see you' or 'good night').
じゃあ今日はこれで終わり。乙、また明日！
Okay, that's it for today. Otsu — see you tomorrow!
チャットが解散するとき、みんな『乙』と書き込んだ。
When the chat dispersed, everyone typed '乙'.