About to behold a monarch hiding (8)

I believe the answer is:

cloaking

'hiding' is the definition.
(thesaurus)

'about to behold a monarch' is the wordplay.
'about' becomes 'c' (abbreviation for circa).
'to behold' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'monarch' becomes 'king' (king is a kind of monarch).
'c'+'lo'+'a'+'king'='CLOAKING'

I've seen this clue in The Daily Express.

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