Firstly, pick hat up for deity (4)

I believe the answer is:

ptah

'for deity' is the definition.
(Ptah is an example)

'firstly pick hat up' is the wordplay.
'firstly' says to take the initial letters.
'up' is a reversal indicator (in down clue: letters go upwards).
The first letter of 'pick' is 'p'.
'hat' back-to-front is 'tah'.
'p'+'tah'='PTAH'

(Another definition for ptah that I've seen is " Ancient deity".)

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

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