Fly, subs. (old).—A familiar; hence, by implication, a parasite or
sucker (q.v.). [In the sixteenth and seventeenth century it was held
that familiar spirits, in the guise of flies, lice, fleas, etc.,
attended witches, who for a price professed to dispose of the power for
evil thus imparted.]
1596. Lodge, Incarnate Devils. This divel prefers an Ephimerides
before a Bible; and his Ptolemey and Hali before Ambrose, golden
Chrisostome, or S. Augustine: promise him a familiar, and he will
take a flie in a box for good paiment.
1610. Ben Jonson, Alchemist i. You are mistaken, doctor, Why he
does ask one but for cups and horses, A rifling fly, none of your
great familiars.
1622. Massinger, Virgin Martyr, ii., 2. Courtiers have flies That
buzz all news unto them.
2. (old).—A printer’s devil; specifically a boy who lifted the printed
sheets from the press. [Now the vibrating frame used for the same
purpose.]
1688. R. Holme, Academy of Armory. These boys do in a
printing-house commonly black and bedaub themselves, when the
workmen do jocosely call them devils, and sometimes spirits, and
sometimes flies.