Nouns

(n)soloany activity that is performed alone without assistance
(n)soloa musical composition for one voice or instrument (with or without accompaniment)
(n)soloa flight in which the aircraft pilot is unaccompanied

Verbs

(v)solofly alone, without a co-pilot or passengers
(v)soloperform a piece written for a single instrument

Adjectives

(s)solocomposed or performed by a single voice or instrument“a passage for solo clarinet”

Adverbs

(r)alone, solo, unaccompaniedwithout anybody else or anything else“the child stayed home alone”, “the pillar stood alone, supporting nothing”, “he flew solo”