Deciphered (4)
'deciphered' is the definition.
('decode' can be a synonym of 'decipher')
This is the entire clue.
'deciphered' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for read that I've seen before include "Interpret writing" , "register" , "Absorbed (written text)" , "Studied" , "Speak" .)