From Wiktionary, the free dictionary
Borrowed from Malayalam ചില്ല് (cillŭ).
chillu (plural chillus)
- (grammar) A type of letter used in Malayalam which does not have an inherent vowel, used to represent a pure consonant without the use of a virama.
- Synonym: chillaksharam
There are five chillus currently in use: ൺ (ṇ), ൻ (ṉ), ർ (ṟ), ൽ (l) and ൾ (ḷ). There are also four archaic ones: ൿ (k), ൔ (m), ൕ (y) and ൖ (ḻ).