Horse-Racing Bet to Determine the First Three Home
Puzzle 17 of National Crossword Day Hard Pack
Question is: Horse-Racing Bet to Determine the First Three Home
and the answer is: TRIFECTA
Word Meaning:
TRIFECTA — (gambling) A bet in which the bettor must select the first three placegetters of a race in the order in which they finish.
Definitions from Wiktionary.