Wiktionary
n. A game in which contestants try to pick up apples out of a large basin of water, using only their mouth.
Wikipedia
Apple bobbing, also known as bobbing for apples, is a game often played on Halloween. The game is played by filling a tub or a large basin with water and putting apples in the water. Because apples are less dense than water, they will float at the surface. Players (usually children) then try to catch one with their teeth. Use of arms is not allowed, and often are tied behind the back to prevent cheating.
In Scotland, this may be called "dooking" (i.e., ducking). In northern England, the game is often called apple ducking or duck-apple.
In Ireland, mainly County Kerry, it is known as "Snap Apple", and in Newfoundland and Labrador, "Snap Apple Night" is a synonym for Halloween.
Usage examples of "apple bobbing".
Duncan said, and swallowed, Adam's apple bobbing in his own throat.
He took the water-jug a servant offered and drank, Adam's apple bobbing.
Young Ian passed a hand over his broxv, Adam's apple bobbing as he swallowed.
He swallowed, his Adam's apple bobbing in his wrinkled, corded throat.
Troy Boren was fidgety and nervous, his hair curly brown, his Adam's apple bobbing up and down as he swallowed repeatedly.