Starring element? (4)

I believe the answer is:

lead

I believe this is a double definition.

'starring' is the first definition.
(as in a lead performer)

'element?' is the second definition.
(lead is a kind of element)

(Other definitions for lead that I've seen before include "guitar accessory?" , "Metal -- Pb" , "writing material" , "Actor playing the principal role" , "Be ahead of - guide" .)

I've seen this clue in The Times.

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