Man entertaining yen to crush King Edward’s army commander (9)
I believe the answer is:
kitchener
'army commander' is the definition.
(Lord Kitchener, 1850-1916)
'man entertaining yen to crush king edward's' is the wordplay.
'man' becomes 'ken' (short for Kenneth).
'entertaining' indicates putting letters inside.
'yen' becomes 'itch' (I've seen this before).
'to crush' says to put letters next to each other (in a down clue, some letters go on top of others).
'king edward' becomes 'er' (abbreviation for Eduardus Rex).
'ken' enclosing 'itch' is 'kitchen'.
'kitchen'+'er'='KITCHENER'
(Other definitions for kitchener that I've seen before include "Old campaigner" , "Old field marshal" , "wartime leader" , "Field Marshal, made Secretary of State for War in 1914, d. 1916 on way to Russia" , "Army leader" .)