Philosophically resigned to the awful cost of holding the line? (5)
I believe the answer is:
stoic
'philosophically resigned' is the definition.
'stoic' can be an answer for 'resigned' (I've seen this before). I am unsure of the 'philosophically' bit.
'the awful cost of holding the line?' is the wordplay.
'the awful' indicates anagramming the letters.
'of holding' becomes 'i' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'the line?' indicates putting letters inside.
'cost' anagrammed gives 'stoc'.
'stoc' enclosing 'i' is 'STOIC'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for stoic that I've seen before include "Uncomplaining in suffering" , "Solemn ceremony" , "Impassive type" , "Unflappable type" , "not given to complaining" .)