The compilers think the word has a Javanese origin. But, when they get to talking about the word's history in India, these are the two incidents they mention:
(Imagine the drama inherent)
""In one of these (Histories if the Rajputs), the eldest son of the Raja of Marwar ran a-muck at the court of Shah Jahan, failing in his blow at the Emperor, but killing five courtiers of eminence before he himself fell.
"Again, in the 18th century, Bijai Singh, also of Marwar, bore strong resentment against the Talpura prince of Hyderabad, Bijar Khan, who had sent to demand from the Rajput tribute anda bride. A Bhatti and a Chondawat offered their services for vengeance, and set out for Sind as envoys. Whilst Bijar Khan read their credentials, muttering, 'No mention of the bride!' the Chondawat buried a dagger in his heart, exclaiming 'This for the bride!' 'And this for the tribute!' cried the Bhatti, repeating the blow. The pair then plied their daggers left and right, and 26 persons were slain before the envoys were hacked to pieces."
How is that for heroism and old-world honor?
Further down the history of the word, which speculates if the notion might have a Malayalam root, itself deriving from 'amokshya' in Sanskrit, they dismiss the suggestion of an Arabic root for the word, saying: "But this is etymology of the kind that scorns history."
I think their attitude, as reflected by this sentence, is proof of their veneration of the Word as capable of being potent bearers of events and influences from ages long past. I like their attitude.
Duart Barbosa's A Description of the Coasts of E. Africa and Malabar in the beginning of the 16th century apparently also has this story:
"There are among them (Javanese) who if they fall ill of any severe illness vow to God that if they remain in good health they will of their own accord seek another more honourable death for his service, and as soon as they get well, they take a dagger in their hands, and go out into the streets and kill as many persons as they meet, both men, women, and children, in such wise that they go like mad dogs, killing until they are killed. These are called Amuco. And as soon as they see them begin this work, they cry out, saying Amuco, Amuco, in order that people may take care of themselves, and they kill them with dagger and spear thrusts."
Damn, I say!