Multiple ways to represent vowellessness[]
Malayalam script is an abugida with vowel അ(/a/)inherent in all consonants. The generic way to represent vowellessness of a consonant, is to use Visible virama(/candrakkala/) following the consonant. Example: ക് (/k/). However, following consonants have another standalone form called Chillu, to represent vowellessness together with a stop or nasal occlusion. Apart from the following consonants no other consonant has Chillu form.
| Consonant | ക | ണ | ന | മ | യ | ല | ള | ഴ | ര | റ |
|---|---|---|---|---|---|---|---|---|---|---|
| Chillu Form | ക് | ണ് | ന് | o (/anuswara/) | 
|
ല് | ള് | ള് | ര് | ര് |
Along with the above mentioned properties, visible virama and Chillus have following interesting and relevant properties.
Visible Virama[]
Depending on the word context, a visible Virama assumes following functions:
To represent the vowel ɨ (IPA)[]
Visible Virama is used to represent closed central unrounded vowel(ɨ) which is called /samvruthokaaram/. Examples:
| Example Word | Type | Pronunciation | Meaning |
|---|---|---|---|
| അവന് | With Visible Virama | /avanɨ/ | for him |
| അവന് | With Chillu form | /avan/ | he |
To represent vowel removal[]
In many <C1, Visible Virama, C2> contexts, visible virama would represent that consonant C1 is forming a conjunct with consonant C2. Simillarly, in many <C1, Visible Virama> contexts, it acts as a inherent അ(/a/) vowel remover. Here it represents phonetic function of vowel remover and graphical function of joiner.
Example: ശബ്ദം = ശബ്ദം. Both meaning sound and pronounced /shabdam/.
To represent vowel removal and non-joining[]
In many <C1, Visible Virama, C2> contexts, visible virama would represent the component word boundary in a composite word. This is the graphical function of boundary seperator(non-joiner) and the phonetic function of removing default vowel from previous consonant.
| Example Word | Type | Pronunciation | Meaning |
|---|---|---|---|
| ദേശ്രാഗം | With Visible Virama | /de:sh'ra:gam/ | raaga desh |
| ദേശ്രാഗം | With sign of ര(/ra/) | /de:shrra:gam/ | meaningless(illegible) |
Chillu[]
Chillu represents vowellessness together with a stop or nasal occlusion. The meaning of some words that use chillu change when the stop is removed by using consonant sign instead of the Chillu.
| Pronunciation | Meaning | ||
|---|---|---|---|
| With Chillu | വന്യവനിക | /van'yavanika/ | big curtain |
| Without Chillu | വന്യവനിക | /vanyavanika/ | wild forest |
However in some other words, meaning does not change between chillu and non-chillu forms. This is comparable to 'color' and 'colour'.
| Pronunciation | Meaning | ||
|---|---|---|---|
| With Chillu | നന്മ | /nanma/ | goodness |
| Without Chillu | നന്മ | /nanma/ | goodness |
Chillu ര് has some special properties described in following sections:
Native user behavior on Chillu ര്[]
Native users always pronounce ര് as RRA_dead; not as RA_dead. Also, they understand Malayalam as a phonetic script. Hence they assume the base letter of ര് as RRA. Because of that, whenever they need to put RRA_dead in writing, they the Chillu ര്.
Multiple base lettersfor Chillu ര്[]
Chillu ര് represents the base character RA(ര) in many Malayalam words as seen in the following examples:
| Combining Words (/...rr + a.../) | അവര് + അല്ല | മലര് + അല്ല |
|---|---|---|
| Resulting combination (/...ra.../) | അവരല്ല | മലരല്ല |
Simillarly, Chillu ര് represents RRA(റ) in some others words:
| Combining Words (/...rr + a.../) | ഞായര് + അല്ല | ചാവേര് + അല്ല | പയര് + അല്ല |
|---|---|---|---|
| Resulting combination (/...rra.../) | ഞായറല്ല | ചാവേറല്ല | പയറല്ല |
While above words are of Dravidian origin, lots of words with Chillu ര് are of Arabic or Urdu origin:
| Combining Words (/...rr + a.../) | കരാര് + അല്ല | ഖദര് + അല്ല |
|---|---|---|
| Resulting combination (/...rra.../) | കരാറല്ല | ഖദറല്ല |
Below are the corresponding scans from a dictionary:
 ചാവേര് in dictionary by C.Madhavan Pillai |
 ഞായര് in dictionary by C.Madhavan Pillai |
 ഖദര് in dictionary by C.Madhavan Pillai |
This indicates that both RA(ര) and RRA(റ) have the same chillu, that is, ര്. Number of words that has chillu ര് from RA(ര) is more than those from RRA(റ). However, the number of words with chillu ര് from റ is significant.