Peer inside nuclear laboratory (4)

I believe the answer is:

earl

'peer' is the definition.
(I know that earl is a type of peer)

'inside nuclear laboratory' is the wordplay.
'inside' says the answer is hidden in the clue.
'EARL' can be found hidden inside 'nuclear laboratory'.

(Other definitions for earl that I've seen before include "... Grey, fragrant Oriental tea" , "Rank below marquess" , "-- Grey, PM 1830-34" , "Jimmy Carter's middle name" , "Noble title" .)

I've seen this clue in the Sydney Morning Herald.

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