Yesterday Mark Liberman posted on this Doonesbury cartoon:
Rich in material. The main thing I want to note (as Mark did) is a sense development in the slang verb rock, from an older sense, around at least since 1990 (‘impact strongly’), to a newer sense, the one in the cartoon, around since at least 2007 (‘wear or display conspicuously or proudly’); this is a change from a more objective sense to a more subjective one, such as Elizabeth Traugott has repeatedly discussed.