Chilantu (pronounced as Chiluntu) is a composite word derived from Chillar + Ubuntu.
Chillar [Hindi] means loose change, like a few cents you throw away at a hopeless beggar in the corner of the street not out of mercy or sympathy but just to get rid of the loose weight of the cents in your purse while retaining only the dollars. In local business markets Chillar is commonly used to refer to small fractional bill amounts which are either rounded down or rounded up.
Ubuntu is the name of a very popular distribution of Linux operating system. It's open source and free of cost as in free beer. Ubuntu is an stubborn OS of choice for many geeks who despise Microsoft Windows.
In local Hindi slang Chilantu refers to a person who is a geek implying he is assumed to have very deep advanced knowledge about some unknown obscure field of study; although being Chilantu also states that he would be considered a fool in his daily activities without using any iota of his knowledge and not producing any result. For example, consider a Ph.D scholar who has not yet completed his thesis in spite of working over it for a decade and he is a poor sick homeless jerk whose wife has also deserted him (pun intended). Such a person is called Chilantu who in spite of such high degree and skill is socially worthless and is often discarded as useless by taxpayers.
I hope I was able to convey the meaning of Chilantu correctly. What is the equivalent word in English having the same meaning?