Diamond \di(a)-mo-nd\ as a girl's name (also used as boy's name Diamond), is pronounced DIE-mund. It is of English origin, and the meaning of Diamond is "of high value; brilliant". The gemstone first used as a given name in the 1890s. The gem is the birthstone for April.
For more information, see also the related name Emerald.
A baby name that sounds like Diamond is Demanda.