Mythical flying dick. The accent is on the last syllable, otherwise it would be a waffle. The вафля is something that will come flying into a mouth that stay yawning for too long (see ловить вафли). The term also describes any flying object with an elongated shape, e.g. Zeppelins.
Как говорится — в такую пасть, только вафли класть.
(Boleron @ pornolab.net, 11/2012)