sheepish (adj.)youdaoicibaDictYouDict[sheepish 词源字典]
c. 1200, "resembling a sheep" in some perceived characteristic, from sheep + -ish. The sense of "bashful, over-modest, awkward among strangers" first is recorded 1690s. Related: Sheepishly; sheepishness. Old English had sceaplic "of a sheep, 'sheep-ly.'"[sheepish etymology, sheepish origin, 英语词源]