Underbelly

underbelly n[sing] 1 undersurface of an animal's body, eg as a cut of meat, esp pork（动物的）下腹部（如切下的一块, 尤指猪肉）. 2 (fig 比喻) area, region, etc that is vulnerable to attack 易受攻击的部位、 区域等 The stock-market crisis struck at the soft underbelly of the US economy, eg its trade deficit. 股市危机打击了美国经济的薄弱环节（如贸易逆差）.