Definitions of matt:

• noun:   the property of having little or no contrast; lacking highlights or gloss
• adjective:   not reflecting light; not glossy

  Example: "A photograph with a matte finish"

• name:  A male given name (common: 1 in 2631 males; popularity rank in the U.S.: #329)
• name:  A surname (rare: 1 in 100000 families; popularity rank in the U.S.: #9105)