gams (n.)youdaoicibaDictYouDict[gams 词源字典]
"legs," 1781, low slang, probably the same word as gamb "leg of an animal on a coat of arms" (1727) and ultimately from Middle English gamb "leg," which is from French (see gammon). Now, in American English slang, especially with reference to well-formed legs of pretty women, but this was not the original sense.[gams etymology, gams origin, 英语词源]