Fugitive deserter, Yankee, keeping poles apart (10)
I believe the answer is:
transitory
'apart' is the definition.
Both the answer and definition are adjectives. Maybe there's an association between them I don't understand?
'fugitive deserter yankee keeping poles' is the wordplay.
'fugitive deserter' becomes 'traitor' (I can't justify this - if you can you should believe this answer much more).
'yankee' becomes 'y' (phonetic alphabet: alpha, bravo, charlie etc.).
'keeping' indicates putting letters inside.
'poles' becomes 'ns' (North and South poles).
'traitor'+'y'='traitory'
'traitory' going around 'ns' is 'TRANSITORY'.
Can you help me to learn more?
(Other definitions for transitory that I've seen before include "Ephemeral" , "Passing" , "Here-today-gone-tomorrow" , "Fleeting" , "Short-lived" .)