Scientist fully prepared to return, abandoning last student (5)

I believe the answer is:

tesla

I'm a little stuck... Click here to teach me more about this clue!

'scientist' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for tesla that I've seen before include "electrical unit" , "Physicist" , "Physics unit" , "Unit of magnetic flux density" , "Nikola ---, electricity pioneer" .)

I've seen this clue in The Telegraph.

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