from
The Collaborative International Dictionary of English v.0.48
Gibbet \Gib"bet\, n. [OE. gibet, F. gibet, in OF. also club, fr.
LL. gibetum;; cf. OF. gibe sort of sickle or hook, It.
giubbetto gibbet, and giubbetta, dim. of giubba mane, also,
an under waistcoat, doublet, Prov. It. gibba (cf. {Jupon});
so that it perhaps originally signified a halter, a rope
round the neck of malefactors; or it is, perhaps, derived fr.
L. gibbus hunched, humped, E. gibbous; or cf. E. jib a sail.]
[1913 Webster]
1. A kind of gallows; an upright post with an arm projecting
from the top, on which, formerly, malefactors were hanged
in chains, and their bodies allowed to remain as a
warning.
[1913 Webster]
2. The projecting arm of a crane, from which the load is
suspended; the jib.
[1913 Webster]