I. ˈsiŋgəltən, -t ə n noun
( -s )
Etymology: French, from English single (I) + French -eton (diminutive suffix)
1. : a card (as in bridge) that is the only one of its suit originally held in a hand — compare doubleton
2. : an individual member or thing distinct from others grouped with it
a quatrain consisting of a triplet and a singleton
the birds scattered … and the singletons were easy to pick up one by one — Thomas Barbour
specifically : a single offspring
in May or June the spotted fawns are born, usually singletons, but rarely twins — W.A.Weber
II. noun
: a mathematical set that contains one element