WordNet sense 1 (a safe place):

refuge

WordNet sense 2 (a device designed to prevent injury):

guard, safety device

WordNet sense 3 (contraceptive device consisting of a sheath of thin rubber or latex that is worn over the penis during intercourse):

condom, prophylactic, rubber, safe

WordNet sense 4 ((baseball) the successful act of striking a baseball in such a way that the batter reaches base safely):

base hit