Where many gather to form a line?

BINGOPARLOR

Think of a lively hall where luck and numbered cards bring crowds together for a classic game.

This clue plays on the double meaning of "line" in bingo culture. In bingo, players aim to complete a straight "line" on their cards, and they gather in a "parlor" to play. The answer combines "bingo" (the game) with "parlor" (the venue), giving "BINGOPARLOR" as the place where people come together to form those winning lines.