Webster's Revised Unabridged Dictionary · 1913

Acockbill

Acockbill ({not transcribed}) , adverb

[Prefix a- + cock + bill: with bills cocked up.]

(a)
(Nautical) Hanging at the cathead, ready to let go, as an anchor.
(b)
(Nautical) Topped up; having one yardarm higher than the other.