a measure of the depth of water taken with a sounding line
"The ship's captain recorded a deep sounding before anchoring in the calm bay."
the act of measuring depth of water (usually with a sounding line)
"The sailor dropped the lead weight to take a sounding and confirm that the ship was in safe waters."
The action of the verb to sound.
"The engineer performed a sounding to measure the depth of the river using a weighted cable."
Test made with a probe or sonde.
In plain English: A sounding is when someone checks how deep something is by dropping an object into it and measuring how long it takes to hit the bottom or feel weighty again.
"We tried several different sounding before settling on the deep baritone."
present participle of sound
"The diver listened to the faint sounding of a whale in the deep ocean."
In plain English: To sound means to make noise by blowing air through your lips, nose, or mouth.
"The judge started sounding out his opinion before making the final ruling."
having volume or deepness
"sounding brass and a tinkling cymbal"
"the sounding cataract haunted me like a passion"
Emitting a sound.
"The whale was emitting a low, haunting sound as it swam deep beneath the surface."
From sound ("produce a sound") + -ing.