Make hard to read, in a way (6)
I believe the answer is:
encode
'make hard to read in a way' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for encode that I've seen before include "Encrypt" , "Encipher" , "Turn message into secret symbols" , "Convert into a cipher" , "Put into cipher" .)