Definitions
An unfavorable card or token, or undesirable or worthless item used as a prize in a contest or game show (such as Let's Make a Deal).
Used in a sentence
“There will always be two doors that hold zonks, so regardless of whether you initially chose the grand prize or a zonk, Monty will always be able to show you a zonk not chosen.”
“A zonk was way overdue, yet the boys knew that the Seniors knew they would think this was a zonk and would trick the boys by making this another real prize.”
“I have three empty coffee cans, two with prizes and one with a slip of paper that says "Zonk."”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Worthless game-show prize”4 letters
02“Knock out”4 letters
Not quite right?
"Search similar patterns."
Z___