标记 (biāo jì) is a general verb and noun for marking something or a mark itself. It differs from 标志 (biāo zhì), which is a distinctive emblem or logo, and from 符号 (fú hào), an abstract symbol like a plus sign. As a verb, 标记 has no direct synonym among these siblings — only 标志 can also be a verb, but with a different sense ('to symbolize').