A ravine or gully, especially in southern Asia.
[Bengali and Hindi nālā, channel, nullah, and similar forms in other Indic languages, all from Middle Indic nāḷa, nāla, hollow stalk, tube, from Sanskrit nāḍaḥ, from naḍaḥ, reed, variant (perhaps influenced by Dravidian words akin to Kannada naḷ, reed) of nadaḥ; akin to Persian nay, reed, flute, Armenian net, arrow, and Hittite nātaš, reed, arrow, and perhaps further akin to Sanskrit nadati, he roars, howls, cries.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.