“Double down” means to commit fully to a risky choice, from blackjack where you...

https://spark-wiki.win/index.php/Hedge_Your_Bets_in_Linguistics:_Meaning,_Origins,_and_Common_Pitfalls

“Double down” means to commit fully to a risky choice, from blackjack where you double your bet for one last card. Learners often think it’s about hesitation or withdrawing—actually, it’s doubling effort, not backing off