dam¹ ◙ for abbreviation 1. decametre(s) • 同decametre或decametresdam² ◙ noun 1. a barrier, typically of concrete, constructed to hold back water and raise its level, the resulting reservoir being used in the generation of electricity or as a water supply • 水坝 (chiefly S. African)an artificial pond or reservoir where rain or spring water is collected for storage • [主南非] 水库 a barrier of branches in a stream, constructed by a beaver to provide a deep pool and a lodge • （海狸筑起的）坝 (chiefly N. Amer.)a rubber sheet used to keep saliva from the teeth during dental operations • [主北美] （牙科手术中的）橡皮障 ◙ (dammed, damming) 1. [with obj.] build a dam across (a river or lake) • 在（河，湖）上筑坝 hold back or obstruct (something) • 阻止；抑制；阻碍 »the closed lock gates dammed up the canal. 关闭的闸门将运河阻断。
【语源】
1. Middle English: from Middle Low German or Middle Dutch; related to Dutch dam and German Damm, also to Old English fordemman 'close up'dam³ ◙ noun 1. the female parent of an animal, especially a domestic mammal • （尤指家养的）母畜，母兽
【语源】
1. late Middle English (denoting a human mother): alteration of dame