Handy name for Walter? (5)

I believe the answer is:

mitty

I'm a little stuck... Click here to teach me more about this clue!

'for walter?' is the definition.
(main character in The Secret Life of Walter Mitty)

'handy name' is the wordplay.
'handy' becomes 'mit' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'name' becomes 'Ty'.
'mit'+'ty'='MITTY'

Can you help me to learn more?

(Other definitions for mitty that I've seen before include "Walter ---, Thurber's fantasist" , "Walter --, Thurber's daydreaming hero" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app