a barrier constructed to hold back water and raise its level, forming a reservoir used to generate electricity or as a water supply

the dam burst after torrential rain

the Hoover Dam

a rubber sheet used to keep saliva from the teeth during dental operations, or as a prophylactic device during cunnilingus and anilingus

build a dam across (a river or lake)

the river was dammed to form Lake Powell

the female parent of an animal, especially a domestic mammal

one version is inherited from the dog's sire and one from its dam

his dam was a pinto mare

decametre(s)

a metric unit of length, equal to 10 metres