battery charger vs charger

battery charger and charger both are nouns.

Word	Noun	Adjective	Verb	Adverb
battery charger	Yes	No	No	No
charger	Yes	No	No	No

As nouns, battery charger and charger are synonyms defined as:

battery charger and charger: a device that can hold a rechargeable battery by means of an electrical cable

battery charger (noun)	charger (noun)
a device that can hold a rechargeable battery by means of an electrical cable	formerly a strong swift horse ridden into battle
	a device that can hold a rechargeable battery by means of an electrical cable