# Consonant - `v::consonant()` - `v::consonant(string $additionalChars)` Similar to `v::alnum()`. Validates strings that contain only consonants: ```php v::consonant()->validate('xkcd'); // true ``` *** See also: * [Alnum](Alnum.md) * [Alpha](Alpha.md) * [Digit](Digit.md) * [Vowel](Vowel.md)