powder horn vs powder flask

powder horn and powder flask both are nouns.

Word	Noun	Adjective	Verb	Adverb
powder horn	Yes	No	No	No
powder flask	Yes	No	No	No

As nouns, powder horn and powder flask are synonyms defined as:

powder horn and powder flask: container for carrying gunpowder; made of the hollow horn of an animal

powder horn (noun)	powder flask (noun)
container for carrying gunpowder; made of the hollow horn of an animal	container for carrying gunpowder; made of the hollow horn of an animal