Boring unusual rites have nothing on me (8)
I believe the answer is:
tiresome
'boring' is the definition.
(synonyms)
'unusual rites have nothing on me' is the wordplay.
'unusual' indicates an anagram.
'have' means one lot of letters go next to another.
'nothing on' becomes 'o' (I've seen this in other clues).
'rites' is an anagram of 'tires'.
'tires'+'o'+'me'='TIRESOME'
(Other definitions for tiresome that I've seen before include "Draggy - unamusing" , "Annoying, being a nuisance" , "wearing" , "Annoying, makes you fed up" , "Tedious and boring" .)