Attribute wrinkled up with time (6)
I believe the answer is:
impute
'attribute' is the definition.
(synonyms)
'wrinkled up with time' is the wordplay.
'wrinkled' is an anagram indicator (I've seen this in other clues).
'with' says to put letters next to each other.
'up' after 'time' is 'timeup'.
'timeup' is an anagram of 'IMPUTE'.
(Other definitions for impute that I've seen before include "Uptime (anag.)" , "'Attribute, assign (6)'" , "Attribute or ascribe - say fault" , "take into account" , "Attribute (something bad) to someone" .)