Source : Webster's Revised Unabridged Dictionary (1913)

Snaffle \Snaf"fle\, n. [D. snavel a beak, bill, snout; akin to
   G. schnabel, OHG. snabul,. sneb, snebbe, OFries. snavel
   mouth, Dan. & Sw. snabel beak, bill, Lith. snapas, and to E.
   snap, v. See {Snap}, and cf. {Neb}.]
   A kind of bridle bit, having a joint in the part to be placed
   in the mouth, and rings and cheek pieces at the ends, but
   having no curb; -- called also {snaffle bit}.

Source : WordNet®

snaffle bit
     n : a simple jointed bit for a horse; without a curb [syn: {snaffle}]