“Double down” comes straight from blackjack—when a player doubles their bet...

https://www.bookmarking-online.win/double-down-comes-straight-from-blackjack-you-double-your-bet-after-seeing

“Double down” comes straight from blackjack—when a player doubles their bet after seeing the first two cards, hoping for a strong hand. Learners often misuse it to mean “just try harder” generally. Nope