Married? Agree to lose initial spirit (6)
I believe the answer is:
mettle
'spirit' is the definition.
(I know that mettle is a type of braveness)
'married? agree to lose initial' is the wordplay.
I cannot quite see how this works, but
'married?' could be 'm' (abbreviation, e.g. in genealogy) and 'm' is located in the answer.
The remaining letters 'ettle' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for mettle that I've seen before include "Courage sounds like iron, for instance" , "Quality" , "Grit" , "The courage to carry on" , "Strength of character, courage" .)