In her soliloquy, Molly Bloom thinks: “hes mad on the subject of drawers thats plain to be seen always skeezing at those brazenfaced things on the bicycles with their skirts blowing up to their navels” (emphasis added, as they say in the trade). Don Gifford’s Ulysses Annotated helpfully tells us that skeezing is “Slang for staring at covertly.” Urban Dictionary, meanwhile, tells us that “skeezing” may have definitionally drifted somewhat, with the top rated definition being “doing the nasty,” and definitions of “skeezer” that impinge female sexuality like about 10,000 other words.
The modern term “creeping,” in the meantime, appears to have taken some of the voyeuristic connotations that Gifford assigns to “skeezing,” albeit in a way that is digitally enabled: “Following what is going on in someone’s life by watching their status messages on Instant Messengers such as MSN. . .”, whereas in the old days you had to do such things in the flesh. Other commentators, however, have such disparate definitions that “creeping” might not actually mean much of anything, other than being a catch-all words of opprobrium.
The Oxford American Dictionary included with OS X doesn’t include an entry for skeezing, and its entry for creeping says “move slowly and carefully, esp. in order to avoid being heard or noticed,” while the noun form does list “a person who behaves in an obsequious way in the hope of advancement,” which seems rather far from what Urban Dictionary thinks.