c.1300 "not detected by sense of hearing," from
un- (1) "not" + pp. of
hear. Meaning "unknown, new" is attested from c.1375 (O.E. had
ungehered in this sense). Usually with
of since 1592. Cf. O.N.
oheyrðr, Dan.
uhørt, M.Du.
ongehoort, O.H.G.
ungehoret.