means Either of the two fleshy folds that form the edges of the mouth — or, by extension, the rim or edge of something like a cup or a wound, and informally, cheeky backtalk.

from An old Germanic body-word, traceable to Old English 'lippa' and kin to Dutch 'lip' and German 'Lippe.' Linguists trace it back to a Proto-Indo-European root meaning 'to lick' or 'to smear,' a cousin of Latin 'labium' (lip) — so the word for the edge of your mouth and the word for what your mouth does to a spoon may share deep roots. The slangy sense of 'giving lip' (cheek, sass) is much later, naming the body part for the talk that comes out of it.