from
The Collaborative International Dictionary of English v.0.48
Jess \Jess\, n.; pl. {Jesses}. [OF. gies, giez, prop. pl. of
giet, get, jet, F. jet, a throwing, jess. See {Jet} a
shooting forth.] (falconry)
A short strap of leather or silk secured round the leg of a
hawk, to which the leash or line, wrapped round the
falconer's hand, was attached when used. See Illust. of
{Falcon}.
[1913 Webster]
Like a hawk, which feeling freed
From bells and jesses which did let her flight.
--Spenser.
[1913 Webster]