D defs.my
Entry 1 sense Webster, 1913

Tasto

/(täs"tō̇)/ · Tas·to · IPA
01 n. A key or thing touched to produce a tone.
  1. 1.
    A key or thing touched to produce a tone.(Mus.)
Phrases & compounds
Tasto solo — single touch; -- in old music, a direction denoting that the notes in the bass over or under which it is written should be performed alone, or with no other chords than unisons and octaves.