State to know of old woman's unfriendly character (3-6)

'unfriendly character' is the definition.
The definition suggests a singular noun which matches the answer.

'state to know of old woman's' is the wordplay.
I cannot really see how this works, but
'state' could be 'ill' (ill is a kind of state) and 'ill' is located in the answer.
'woman's' could be 'her' (belonging to a woman) and 'her' is located in the answer.
'know of old' could be 'wis' (I've seen this before) and 'wis' is present in the answer.
No letters remain.
This explanation may well be incorrect...

Can you help me to learn more?