Applied from royal spread (7)
I believe the answer is:
exerted
'applied' is the definition.
(exerting is a kind of applying)
'from royal spread' is the wordplay.
'from' becomes 'ex' ('from' in Latin).
'royal' becomes 'er' (abbreviation for Elizabeth Regina).
'spread' becomes 'ted' (I've seen this in another clue).
'ex'+'er'+'ted'='EXERTED'
(Other definitions for exerted that I've seen before include "Made a great physical effort" , "Brought to bear, influence perhaps" .)