Fat and foolish said Poe (7)
I believe the answer is:
adipose
'fat' is the definition.
(similar in meaning)
'foolish said poe' is the wordplay.
'foolish' indicates anagramming the letters.
'said'+'poe'='saidpoe'
'saidpoe' anagrammed gives 'ADIPOSE'.
'and' is the link.
(Other definitions for adipose that I've seen before include "Fat-storing (tissue)" , "Of tissue, fatty in substance" , "Of animal, fat, fatty" , "Is a dope fat?" , "Like a sort of fat" .)