hallmark vs earmark

hallmark and earmark both are nouns.

Word	Noun	Adjective	Verb	Adverb
hallmark	Yes	No	No	No
earmark	Yes	No	Yes	No

As nouns, hallmark and earmark are synonyms defined as:

hallmark and earmark: a distinctive characteristic or attribute of someone or something

Other synonyms of hallmark include stylemark, trademark.

hallmark (noun)	earmark (noun)
a distinctive characteristic or attribute of someone or something	a distinctive characteristic or attribute of someone or something
a mark on an article of trade to indicate its origin and authenticity	identification mark on the ear of a domestic animal

hallmark (verb)	earmark (verb)
	give or assign a resource to a particular person or cause