Companion of castaway fellow freed a Yorkshireman's capital (6)
I believe the answer is:
friday
'companion of castaway' is the definition.
'friday' can be an answer for 'companion' (I have seen 'faithful companion' mean 'friday' so perhaps 'companion' could also mean 'friday'). I am not certain of the 'of castaway' bit.
'fellow freed a yorkshireman's capital' is the wordplay.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'freed' becomes 'rid' (I've seen this in another clue).
'capital' indicates taking the first letters.
The first letter of 'yorkshireman' is 'y'.
'f'+'rid'+'a'+'y'='FRIDAY'
Can you help me to learn more?
(Other definitions for friday that I've seen before include "Crusoe's companion" , "Its child is loving and giving" , "Crusoe's Man (Defoe)" , "one of Chesterton's, so-called" , "An islander" .)