Loving a second royal, ring us (7)
I believe the answer is:
amorous
'loving' is the definition.
(similar in meaning)
'a second royal ring us' is the wordplay.
'second' becomes 'mo' (both are short periods of time).
'royal' becomes 'r' (common abbreviation e.g. RM - Royal Marine).
'ring' becomes 'O' (letter resembling a ring).
'a'+'mo'+'r'+'o'+'us'='AMOROUS'
(Other definitions for amorous that I've seen before include "Inclined towards displaying love" , "Possessed of loving or romantic feeling" , "Sexy" , "Lustful" , "Showing desire" .)