The Collaborative International Dictionary of English v.0.48:

Stretto \Stret"to\, n. [It., close or contacted, pressed.]
   (Mus.)
   (a) The crowding of answer upon subject near the end of a
       fugue.
   (b) In an opera or oratorio, a coda, or winding up, in an
       accelerated time. [Written also stretta.]
       [1913 Webster]