Noun

• S: (n) geminate (a doubled or long consonant) "the `n' in `thinness' is a geminate"
• direct hypernym / inherited hypernym / sister term

Verb

• S: (v) reduplicate, geminate (form by reduplication) "The consonant reduplicates after a short vowel"; "The morpheme can be reduplicated to emphasize the meaning of the word"
• S: (v) pair, geminate (occur in pairs)
• S: (v) pair, geminate (arrange in pairs) "Pair these numbers"
• S: (v) geminate (arrange or combine in pairs) "The consonants are geminated in these words"