singleton

1. A playing card that is the only one of its suit in a hand, especially at bridge.

   the playing card that is the only card in a suit held in a bridge hand as initially dealt

2. A hand containing only one card of a certain suit.

3. A single object, especially one of a group.

   элеме́нтelemént

   a single object (as distinguished from a pair)

4. A class that may not be instantiated more than once, i.e. that implements the singleton design pattern.

   Singleton

5. A set with exactly one element.

   einelementige Menge, Einermenge

   a set containing a single member

6. A child or animal that is born singly, not as a twin or other multiple birth.

   singleton preterm birth

7. A person without a romantic partner.

8. A person without a dissociative identity.

9. A single consonant, as opposed to a geminated consonant.

   singleton sonorants

10. Synonym of blot.

11. A class offered only once within a school year.

regular