Resin on my royal right hand! (5)
I believe the answer is:
myrrh
'resin' is the definition.
(myrrh is a kind of resin)
'on my royal right hand' is the wordplay.
'on' is a charade indicator (letters next to each other).
'royal' becomes 'r' (common abbreviation e.g. RM - Royal Marine).
'right hand' becomes 'RH' (medical abbreviation).
'my' put next to 'r' is 'myr'.
'myr'+'rh'='MYRRH'
(Other definitions for myrrh that I've seen before include "The Three Wise Men brought Jesus gifts of gold, frankincense and . . . . ." , "birthday gift" , "Aromatic gum" , "Bitter tree gum, used in perfume and incense" , "fragrant substance" .)