Expressionless lifeless god (7)

I believe the answer is:

deadpan

'expressionless' is the definition.
(I know that expressionless can be written as deadpan)

'lifeless god' is the wordplay.
'lifeless' becomes 'dead' (synonyms).
'god' becomes 'pan' (Pan is a Greek god).
'dead'+'pan'='DEADPAN'

(Other definitions for deadpan that I've seen before include "Showing no expression" , "Blank" , "Keeping a straight face" , "With expressionless face" , "Poker-faced" .)

I've seen this clue in The Globe and Mail.

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