The Collaborative International Dictionary of English v.0.48:

Fit \Fit\, n. [AS. fitt a song.]
   In Old English, a song; a strain; a canto or portion of a
   ballad; a passus. [Written also fitte, fytte, etc.]
   [1913 Webster]

         To play some pleasant fit.               --Spenser.
   [1913 Webster]