1. OE. a-, originally ar- (rarely preserved, as in ar-æfnan), OHG. ar-, ir- ur- (mod. G. er-), Goth. us- ur-, implying motion onward or away from a position, hence away, on, up, out, and thus with verbs of motion adding intensity; as in a-bide, a-go, a-rise, a-wake, and many obs. verbs; after the analogy of which it was subsequently prefixed to other vbs., not found with it in OE., as a-curse.