English monarch seen in public, showing strain (9)
I believe the answer is:
overexert
'strain' is the definition.
(thesaurus)
'english monarch seen in public' is the wordplay.
'english' becomes 'e' (abbreviation).
'monarch' becomes 'rex' (I've seen this before**).
'seen in' indicates putting letters inside.
'public' becomes 'overt' ('overt' is associated in meaning with 'public').
'e'+'rex'='erex'
'erex' going into 'overt' is 'OVEREXERT'.
'showing' is the link.
(Other definitions for overexert that I've seen before include "work too hard" , "strain" , "use too much" , "exercise unduly?" , "Make too much effort" .)