Answer: blacktie

AnswerCrossword Clue
BLACKTIE

Semiformal, as an affair

BLACKTIE

Semiformal

BLACKTIE

Formal

BLACKTIE
Fairly formal
BLACKTIE
Formal indication
BLACKTIERequiring a dinner jacket
BLACKTIEFormal-affair wear
BLACKTIEEvening wear.
BLACKTIEOrder of dress.
BLACKTIEFormal wear
BLACKTIEFormal, but not too
BLACKTIEPhrase on some invitations
BLACKTIEFund-raiser wear, perhaps
BLACKTIELike some formal events
BLACKTIEFormal attire