From WordNet (r) 2.0 (August 2003) [wn]:
headless
adj 1: not having a head or formed without a head ; "the headless
horseman"; "brads are headless nails" [ant: headed]
2: not using intelligence [syn: brainless]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Headless \Head"less\, a. [AS. he['a]fodle['a]s.]
1. Having no head; beheaded; as, a headless body, neck, or
carcass.
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2. Destitute of a chief or leader. --Sir W. Raleigh.
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3. Destitute of understanding or prudence; foolish; rash;
obstinate; mindless. [Obs.]
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Witless headiness in judging or headless hardiness
in condemning. --Spenser.
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