Melatonin - Sleep triggering hormone which controls the circadian rhythm. Also check out Melatonin Side Effects .
mala-ta-taan-iN or mela-taan-iN or mil-ta-taan-iN
mal - to soil, to make dirty, to make it dark, to blacken it, to become "dark" (taamsic) or lazy, dull, sleepy (so when people rub their eyes, in Sanskrit and Hindi it is called "aankhe or akSh malana", to clear the substance that makes your eyes sleepy, or even "aankhe or akSh milana", as when you are sleepy, your eye lids start drooping and meet.
mil - to meet
mela or mila for noun.
ta - for Present or Past Participle
taan - to stretch, to relax, to ease the body
iN - suffix for Adjective.
Is is strange that such good coincidences are there or just that the human thought is so limited, shallow or prone to wild imaginations, which I do not agree, but someone may think so, but he or she should reserve that comment after he or she takes the trouble of getting in trained in Sanskrit, atleast the approaching 300 rules of Sandhis or the Euophonic rules.
Circadian Rhythm
The 24 hour Body Cycle that also regulates your Sleep and Awake cycles. The Pineal Gland in your body regulates this and is synchronized with the Solar Day and Night Cycle.
"C" can be "Palatal Sibiliant", "Cererbal Sibiliant", or used as "k" (but why then you would not use "k" instead?). We will take "C" as "Sh", which is Cererberal Sibiliant sound, and others are "s" Dental Sibiliant, "Z" or "Ch" is used to note the Palatal Sibiliant. Note that in Dental "s", the tounge touches the teeth (almost), in Palatal "s" it touches the root of the mouth, and in Cerberal "S" it curls up backwards in the mouth.
ShiRSh-aadhiin
ShiRSh- Head
aadhiin - dependent
Something is dependent on the head or in in the head or controlled by the head - the sleep and waking cycle!