Called me Dan, mistakenly (5)
I believe the answer is:
named
'called' is the definition.
('name' can be a synonym of 'call')
'me dan mistakenly' is the wordplay.
'mistakenly' is an anagram indicator.
'me'+'dan'='medan'
'medan' is an anagram of 'NAMED'.
(Other definitions for named that I've seen before include "Designated" , "Handled" , "Entitled" , "Christened" , "Titled" .)