n. pl. un·der·bel·lies 1. The soft belly or underside of an animal's body. Also called underbody. 2. The bottom side or part: scraped the car's underbelly going over the curb. 3. The vulnerable or weak part or aspect: "What if quantum theory is wrong? This is the soft underbelly of the whole project of quantum gravity" (Lee Smolin). 4. The corrupt or immoral part or aspect: "[a novel] that most effectively exposed the decadent underbelly of corporate high tech" (Theodore Roszack). |
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