SACEUR vs commanding officer

SACEUR and commanding officer both are nouns.

Word	Noun	Adjective	Verb	Adverb
SACEUR	Yes	No	No	No
commanding officer	Yes	No	No	No

As nouns, commanding officer is a hypernym of SACEUR; that is, commanding officer is a word with a broader meaning than SACEUR:

SACEUR: commanding officer of ACE; NATO's senior military commander in Europe
commanding officer: an officer in command of a military unit

Other hypernyms of SACEUR include commandant, commander.

SACEUR (noun)	commanding officer (noun)
commanding officer of ACE; NATO's senior military commander in Europe	an officer in command of a military unit