n., v., & adv.
n. (pl. -os) 1 (pl. -os or soli) a a vocal or instrumental piece or passage, or a dance, performed by one person with or without accompaniment. b (attrib.) performed or performing as a solo (solo passage; solo violin). 2 a an unaccompanied flight by a pilot in an aircraft. b anything done by one person unaccompanied. c (attrib.) unaccompanied, alone. 3 (in full solo whist) a a card-game like whist in which one player may oppose the others. b a declaration or the act of playing to win five tricks at this.
v. (-oes, -oed) 1 intr. perform a solo, esp. a solo flight. 2 tr. perform or achieve as a solo.
adv. unaccompanied, alone (flew solo for the first time). solo stop an organ stop especially suitable for imitating a solo performance on another instrument.
[ It. f. L solus alone ]