bulla

bulla
[ˈbʊlə]
(pl. bullae ˈbʊliː)
  1. (Medicine)a bubble-like cavity filled with air or fluid, in particular
    (医)大泡,大水(或脓)疱,尤指
    ■a large blister containing serous fluid
    大(水)疱
    ■an abnormal air-filled cavity in the lung
    肺(气肿)大泡
  2. (Anatomy)a rounded prominence
    (剖)圆凸物
  3. a round seal attached to a papal bull, typically one made of lead
    (罗马教皇的)印玺(尤指铅制的)
语源
  1. Latin, literally bubble'
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