1911 Encyclopædia Britannica/Fast and Loose

FAST AND LOOSE, a cheating game played at fairs by sharpers. A strap, usually in the form of a belt, is rolled or doubled up with a loop in the centre, and laid edgewise on a table. The swindler then bets that the loop cannot be caught with a stick or skewer as he unrolls the belt. As this looks to be easy to do the bet is often taken, but the sharper unrolls the belt in such a manner as to make the catching of the loop practically impossible. Centuries ago it was much practised by gipsies, a circumstance alluded to by Shakespeare in Anthony and Cleopatra (iv. 12):

“Like a right gipsy, hath, at fast and loose,
Beguiled me to the very heart of loss.”

From this game is taken the colloquial expression “to play fast and loose.” At the present day it is called “prick the garter” or “prick the loop.”