- the lower, posterior part of an animal's belly
- any vulnerable or unprotected area, region, point, etc.
See underbelly in American Heritage Dictionary 4
noun pl. un·der·bel·lies
- The soft belly or underside of an animal's body. Also called underbody.
- The vulnerable or weak part: “So much . . . can be learned from these and other neglected sources from the underbelly of traditional scholarship” (Stephen Jay Gould).
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