In one of Al's famous celebrity interviews made for AL-TV, Ozzy Osbourne is heard to say "Now what the heck is a hammysync?"

In this picture, we see a Hemi-Sync Synthesizer, a device which generates beta and theta waves to enable synchronizing the left and right hemispheres of the brain to reach a state of alertness or relaxation. A "hemi sync" occurs when the person reaches that state.

It's probable that Ozzy was referring to the above biofeedback procedure (used as a therapuetic tool) and his thick accent turned the words into "hammy" sync!