Definitions for "dateless"
unaffected by time; "few characters are so dateless as Hamlet"; "Helen's timeless beauty"
having no known beginning and presumably no end; "the dateless rise and fall of the tides"; "time is endless"; "sempiternal truth"
Keywords:  prom, companion, occasion, social
not having a social companion for an occasion; as, to be dateless for the prom.
of such great duration as to preclude the possibility of being assigned a date; "dateless customs"
Keywords:  letter, bearing
not bearing a date; "a dateless letter"
Keywords:  fixed, time
Without date; having no fixed time.