DATU

n. dato, chief of a Malay tribe; chief of a barrio

Datu or datto is the title for ancient tribal chieftains and monarchs in pre-Hispanic Philippines. Together with sultan and raja, they are also titles of royalty and currently used in Malaysia, Brunei, Philippines and Indonesia. These titles are the equivalent of European dukes and  marquesses. The word datu was derived from two Malay words: dato' or datok, which are royal titles of the Malays. The myth of the arrival of ten Bornean datus is celebrated in the Binirayan festival in the island of Panay, which in ancient times was known as the island of "Aninipay".
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Direct Access Test Units (DATUs) are special PSTN phone numbers that terminate at the central office switch in a telephone company's local exchange that provide switchmen and telco technicians with a circuit for testing lines in various ways. Among the many things a DATU can do are:Make certain electrical connections, such as shorting a line's tip to ring, tip to ground, or ring to ground.Play certain tones on the line (high tone, low tone) to test the line's audio circuit.Monitor the audio circuit on the line if it is in use (though this only provides a scrambled rendition of the line's audio circuit for privacy and security reasons).Create and modify certain variables such as counters and timers on the CO switch, as well as adding and modifying exchanges.Remove a line from permanent signal holding state.
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k.r(in some region only) title of headman