# Countable

[koun-tuh-buh l] /ˈkaʊn tə bəl/

**adjective**

1.

able to be counted.

2.

Mathematics.

/ˈkaʊntəbəl/

**adjective**

1.

capable of being counted

2.

(maths, logic) able to be counted using the natural numbers; finite or denumerable

3.

(linguistics) denoting a count **noun**

mathematics

A term describing a set which is isomorphic to a subet of the natural numbers. A countable set has “countably many” elements. If the isomorphism is stated explicitly then the set is called “a counted set” or “an enumeration”.

*Examples* of countable sets are any finite set, the natural numbers, integers, and rational numbers. The real numbers and complex numbers are not [proof?].

(1999-08-29)

Tagged: c

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countable

- Count against
verb 1. (intransitive, preposition) to have influence to the disadvantage of: your bad timekeeping will count against you Be disadvantageous to, as in His earnings this year will count against his Social Security benefits. This idiom uses count in the sense of “make a reckoning,” in this case negative. [ Early 1900s ]