First of physicists in the lab, a kooky set of characters (8)
I believe the answer is:
alphabet
'set of characters' is the definition.
(I've seen this before)
'first of physicists in the lab a kooky' is the wordplay.
I cannot really understand how this works, but
'first' could be 'alpha' and 'alpha' is found in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
The remaining letters 'be' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for alphabet that I've seen before include "Pale bath (anag.)" , "series of letters" , "Fundamental language components" , "Whole set of letters" , "Confusing assortment of initials" .)