Measure concentration with a limited sounding value (7)
I believe the answer is:
titrate
'measure' is the definition.
(I know that titrate is a more specific form of measure)
'concentration with a limited sounding value' is the wordplay.
'concentration' becomes 'titre' (titre is a kind of concentration).
'with' indicates putting letters inside.
'a limited sounding value' becomes 'at' (I can't explain this - if you can you should give a lot more credence to this answer).
'titre' going around 'at' is 'TITRATE'.
Can you help me to learn more?
(Other definitions for titrate that I've seen before include "Experimental way to measure" , "Carry out scientific analysis" , "Use indicator maybe" , "Measure the strength of (a solution) using a reagent" , "measure volume" .)