hap (n.) Look up hap at Dictionary.com
c. 1200, "chance, a person's luck, fortune, fate;" also "unforeseen occurrence," from Old Norse happ "chance, good luck," from Proto-Germanic *hap- (source of Old English gehæp "convenient, fit"), from PIE *kob- "to suit, fit, succeed" (cognates: Sanskrit kob "good omen; congratulations, good wishes," Old Irish cob "victory," Norwegian heppa "lucky, favorable, propitious," Old Church Slavonic kobu "fate, foreboding, omen"). Meaning "good fortune" in English is from early 13c. Old Norse seems to have had the word only in positive senses.
hap (v.) Look up hap at Dictionary.com
"to come to pass, be the case," c. 1300, from hap (n.) "chance, fortune, luck, fate," or from Old English hæppan.