Battle-axe? King and I protected by tough one (8)
I believe the answer is:
harridan
'battle-axe?' is the definition.
(I've seen this before)
'i protected by tough one' is the wordplay.
'i' becomes 'ri' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'protected by' indicates putting letters inside.
'tough' becomes 'hard' ('hard' is associated in meaning with 'tough').
'one' becomes 'an' (I've seen this in other clues).
'ri' going into 'hard' is 'harrid'.
'harrid'+'an'='HARRIDAN'
'king and' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for harridan that I've seen before include "Vixen" , "Shrewish old woman" , "nasty old woman" , "Old woman scold" , "Virago -- rain hard (anag)" .)