J for jalam

J for jalam
ஜலம் means water
ஜ=ja
ல=la
ம்=m
Although Tamil script does not have the consonant ja, there are some special consonants as described in an earlier post that are used to write words of foreign origin like jalam (which is a sanskrit word for water).
ஜனனி(janani-mother)
Some people prefer to use Tamil consonants instead of these derived consonants to maintain the purity of the language.
If we compare the Tamil consonants compared to that of other Indian language scripts like Hindi, Telugu, Kannada etc, Tamil has only 18 consonants. While the ja series in other languages have four sounds, Tamil has just one letter to cover all of them
cha Cha ja jha(च छ ज झ)
ச - sa/cha-is used for sa and cha
So the foreign consonant ஜ is used to for ja and jha
sanikkizhamai(saturday)
சனிக்கிழமை
கிழமை - is day