twin prime

Noun

 * 1)  Either of a pair of prime numbers that differ by two.
 * 5 and 7, and 191 and 193, are pairs of twin primes.

Usage notes

 * 2 and 3 are not generally considered to be twin primes, although they appear in a cluster, since 2 is the only even prime number so two consecutive prime numbers cannot differ by 1.

Translations

 * Icelandic: frumtalnatvíburi, tvíburafrumtala
 * Spanish: primo gemelo
 * Swedish: tvillingprimtal,