Something that is buff is pale brown in colour.
He took a largish buff envelope from his pocket.
他从口袋里拿出一个相当大的浅棕色信封。
buffs
You use buff to describe someone who knows a lot about a particular subject. For example, if you describe someone as a film buff, you mean that they know a lot about films.
Judge Lanier is a real film buff.
拉尼尔法官是个真正的电影迷。