Physicist who gave us a modern measure of weight (6)
I believe the answer is:
newton
'physicist' is the definition.
(Sir Isaac Newton)
'gave us a modern measure of weight' is the wordplay.
I cannot really understand how this works, but
'modern' could be 'new' (associated in meaning) and 'new' is found within the answer.
'measure' could be 'ton' (ton is a kind of measure) and 'ton' is located in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'who' acts as a link.
Can you help me to learn more?
(Other definitions for newton that I've seen before include "Isaac . . . . . ., great English physicist who discovered gravity" , "Thandie - - , actress" , "inclined to apply discovery?" , "Sir Isaac . . . . . ., great English mathematician" , "Famous mathematician" .)