Note: The adjective slipper has been effectively replaced by its derivative slippery, though the former was in existence in dialect late enough to be noticed by the Survey of English Dialects, which recorded it in Devon and Cornwall (see Survey of English Dialects: The Dictionary and Grammar, Routledge, 1994, s.v.). — The Germanic verb has been compared with Greek olibrón, glossed by Hesychius with olisthērón "slippery," though the assumption of an Indo-European etymon *h₃slib-ro-, with both *b and a laryngeal preceding a sibilant, seems questionable. Parallel to *sleipan- is a verb *sleupan- "to creep, glide," which has been explained as a secondary formation based on near-synonymous *sleuban- (see slip entry 5, sleeve). As all these bases are ultimately of phonesthemic origin and can presumably be reshaped by variation of phonesthemic origin, it is difficult to disentangle inheritance from innovation. Compare slip entry 1.