adjective
Without a head (body part).
Without a head (hardware or device feature).
Without leadership.
(linguistics, of a phrase or compound) Not having a head morpheme or word.
(computing) Running without a graphical user interface; running without any attached output device (e.g., monitor) or input device (e.g., keyboard, mouse).
(of beer) Without a head of foam.
(obsolete) Heedless.
(obsolete, firearms) Rimless, not having a cartridge case rim (flange).