What is the meaning of Singleton?

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

A hand containing only one card of a certain suit.

A single object, especially one of a group.

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

A set with exactly one element.

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

A person without a romantic partner.

A person without a dissociative identity.

A single consonant, as opposed to a geminated consonant.

Synonym of blot

a singleton (lone playing card)

a singleton (design pattern, class, set)

card games singleton

mathematics singleton

computing singleton

singleton (class that may not be instantiated more than once)

singleton

Source: wiktionary.org