Proto-Nilgiri : *aṭ
Meaning : ditch; cliff
Kota : aṭ "ditch, ravine; perpendicular cliff"
Toda : oṭ "cliff (song word; said to be < Badaga haṭṭu)"
Notes : Despite the comment about the Toda word, it obviously belongs together with the Kota form, but further etymology is unclear.
Number in DED : 101