sin·gle·ton 
(sĭnggəl-tən)
(sĭnggəl-tən)n.
1. One that is single, especially:
a. A child or animal born as a single birth, especially in contrast to one that is part of a multiple birth.
b. A playing card that is the only one of its suit in a player's hand.
c. An unmarried person.
d. Linguistics A nongeminate consonant.
2. An individual separated or distinguished from two or more of its group.
[From the name Singleton (influenced by SINGLE).]