This contrasts with a morpheme, which is the smallest unit of meaning but may not stand on its own. A word may consist of a single morpheme (for example: "oh!, rock, red, quick, run, expect"), or several ("rocks, redness, quickly, running, unexpected"), whereas a morpheme may not be able to stand on its own as a word (in the words just given, these are "-s, -ness, -ly, -ing, un-, -ed").