Out of one's head; deranged. / (Britain, dialect, slang) Thick-headed.

Without a date imprinted, assigned, or associated. / Having no date—a meeting with a lover or potential lover. / Timeless; immortal / Without a start; immemorial / (archaic) Without an end; endless

The state or condition of being dateless: timeless or undated. / The state or condition of being dateless: without a date (romantic partner).