echolocation vs echo sounding

echolocation and echo sounding both are nouns.

Word	Noun	Adjective	Verb	Adverb
echolocation	Yes	No	No	No
echo sounding	Yes	No	No	No

As nouns, echolocation and echo sounding are synonyms defined as:

echolocation and echo sounding: determining the location of something by measuring the time it takes for an echo to return from it

echolocation (noun)	echo sounding (noun)
determining the location of something by measuring the time it takes for an echo to return from it	determining the location of something by measuring the time it takes for an echo to return from it