2.PhraseIndicating acceptance, indulgence, or insouciance: Why not? Who cares?"It’s expensive, but what the hell, you only live once.; Surprisingly, dieters ate more ice cream after eating a large milkshake than after eating a small one. Dr. Polivy calls this the “What the hell” effect, which she describes as thinking “What the hell, my diet’s already broken, so I might as well eat everything in sight.”"