adjective
always used before a noun :not having or including another :only one
not married or not having a serious romantic relationship with someone
used for emphasis after words like any, each, every, etc.
always used before a noun :made for one person to use
Brit :one-way
noun
plural singles
[count] :an unmarried person and especially one who is young and socially active - usually plural
[count] a baseball :a hit that allows the batter to reach first base
b cricket :a hit that scores one run
singles [plural] :a game of tennis or a similar sport that is played between two players
[count] :a music recording having one main song and sometimes one or more other songs
[count] :a room in a hotel, inn, etc., for one person
[count] US :a one-dollar bill
[count] Brit :a one-way ticket
verb
singles; singled; singling
[no obj] :to hit a single in baseball
single out
[phrasal verb]
single out (someone or something) or single (someone or something) out :to treat or to speak about (someone or something in a group) in a way that is different from the way you treat or speak about others