Attribute that makes a writer (7)
I believe the answer is:
ascribe
'attribute' is the definition.
(I know that attribute can be written as ascribe)
'a writer' is the wordplay.
'writer' becomes 'scribe' (scribe is a kind of writer).
'a'+'scribe'='ASCRIBE'
'that makes' acts as a link.
(Other definitions for ascribe that I've seen before include "'Impute, assign (7)'" , "Attribute to, say, an old writer?" , "put down" , "Attribute to specified source or cause" , "'Attribute, assign (7)'" .)