diminution

(dĭmˌə-no͞oˈshən, -nyo͞oˈ-)

1. a. The act or process of diminishing; a lessening or reduction.
   b. The resulting reduction; decrease.
2. Music Statement of a theme in notes of lesser duration, usually one-half, of the original.

Related Forms:

• dimˌi·nuˈtion·al adjective