I'm sly perhaps, and slippery (5)
I believe the answer is:
slimy
'slippery' is the definition.
(similar in meaning)
'i'm sly perhaps' is the wordplay.
'perhaps' indicates an anagram.
'im'+'sly'='imsly'
'imsly' anagrammed gives 'SLIMY'.
'and' is the link.
(Other definitions for slimy that I've seen before include "Glutinous" , "Oleaginous" , "Moist and slippery" , "toadying" , "Covered with slippery stuff, say mud" .)