emblem vs Cross

emblem and Cross both are nouns.

Word	Noun	Adjective	Verb	Adverb
emblem	Yes	No	No	No
Cross	Yes	No	No	No

As nouns, Cross is a hyponym of emblem; that is, Cross is a word with a more specific, narrower meaning than emblem:

emblem: special design or visual object representing a quality, type, group, etc.
Cross: a representation of the structure on which Jesus was crucified; used as an emblem of Christianity or in heraldry

Other hyponyms of emblem include colophon, colors, colours, crest, device, flag, heraldry, skull and crossbones, totem, totem pole.

emblem (noun)	Cross (noun)
special design or visual object representing a quality, type, group, etc.	a representation of the structure on which Jesus was crucified; used as an emblem of Christianity or in heraldry
a visible symbol representing an abstract idea