dam

Multiple Entries:
  dam    decametre  

Concise Oxford English Dictionary © 2008 Oxford University Press:
dam1

▶noun

• 1 a barrier constructed to hold back water and raise its level, forming a reservoir or preventing flooding.

  ■ a barrier of branches in a stream, constructed by a beaver to provide a deep pool and a lodge.

• 2 (also dental dam) a rubber sheet used to keep saliva from the teeth during dental operations, or as a prophylactic device during cunnilingus and anilingus.

▶verb (dammed, damming) build a dam across.

■ hold back or obstruct.

– origin ME: from Mid. Low Ger. or MDu.; rel. to OE fordemman ‘close up’.

Concise Oxford English Dictionary © 2008 Oxford University Press:
dam2

▶noun the female parent of an animal, especially a mammal.

– origin ME: alt. of dame.

Concise Oxford English Dictionary © 2008 Oxford University Press:
dam3

▶abbreviation decametre(s).

Concise Oxford English Dictionary © 2008 Oxford University Press:
decametre /ˈdekəmiːtə(r)/ (US decameter, dekameter) (abbrev.: dam; US also dkm)

▶noun a metric unit of length, equal to 10 metres.

– derivatives
decametric adjective.