Source : Webster's Revised Unabridged Dictionary (1913)

Soli \So"li\, n.,
   pl. of {Solo}.

Solo \So"lo\, n.; pl. E. {Solos}, It. {Soli}. [It., from L.
   solus alone. See {Sole}, a.] (Mus.)
   A tune, air, strain, or a whole piece, played by a single
   person on an instrument, or sung by a single voice.

Source : WordNet®

solo
     adj : composed or performed by a single voice or instrument; "a
           passage for solo clarinet"
     [also: {soli} (pl)]

solo
     n 1: any activity that is performed alone without assistance
     2: a musical composition for one voice or instrument (with or
        without accompaniment)
     3: a flight in which the aircraft pilot is unaccompanied
     [also: {soli} (pl)]

solo
     adv : without anybody else; "the child stayed home alone"; "he
           flew solo" [syn: {alone}, {unaccompanied}]
     v 1: fly alone, without a co-pilot or passengers
     2: perform a piece written for a single instrument
     [also: {soli} (pl)]

soli
     See {solo}