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1. A sensory system in certain animals, such as bats and dolphins, in which usually high-pitched sounds are emitted and their echoes interpreted to determine the direction and distance of objects.
2. ElectronicsA process for determining the location of objects by emitting sound waves and analyzing the waves reflected back to the sender by the object.In both senses also calledecho ranging.
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.