cardamon vs cardamum

cardamon and cardamum both are nouns.

Word	Noun	Adjective	Verb	Adverb
cardamon	Yes	No	No	No
cardamum	Yes	No	No	No

As nouns, cardamon and cardamum are synonyms defined as:

cardamon and cardamum: aromatic seeds used as seasoning like cinnamon and cloves especially in pickles and barbecue sauces

Other synonyms of cardamon include cardamom.

cardamon (noun)	cardamum (noun)
aromatic seeds used as seasoning like cinnamon and cloves especially in pickles and barbecue sauces	aromatic seeds used as seasoning like cinnamon and cloves especially in pickles and barbecue sauces
rhizomatous herb of India having aromatic seeds used as seasoning