Physicist with deal for the lecturer? (6)

I believe the answer is:

planck

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'physicist' is the definition.
(I know that Planck is a physicist)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for planck that I've seen before include "German physicist giving name to a constant" , "Max --, German scientist, gave name to a constant" , "German physicist, initiator of quantum theory, d. 1947" , "Max ---, quantum theorist" .)

I've seen this clue in The Times.

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