Conceal ring found with us - it's ugly (7)
I believe the answer is:
hideous
'ugly' is the definition.
(similar in meaning)
'conceal ring found with us' is the wordplay.
'conceal' becomes 'hide' (synonyms).
'ring' becomes 'O' (O is the shape of a ring).
'found with' says to put letters next to each other.
'hide'+'o'+'us'='HIDEOUS'
'it's' acts as a link.
(Other definitions for hideous that I've seen before include "Extremely ugly" , "Frightful" , "Horrible" , "Unsightly" , "revolting" .)