brown algae vs tang

brown algae and tang both are nouns.

Word	Noun	Adjective	Verb	Adverb
brown algae	Yes	No	No	No
tang	Yes	No	No	No

As nouns, tang is a hyponym of brown algae; that is, tang is a word with a more specific, narrower meaning than brown algae:

brown algae: algae having the chlorophyll masked by brown and yellow pigments
tang: brown algae seaweed with serrated edges

brown algae (noun)	tang (noun)
algae having the chlorophyll masked by brown and yellow pigments	any of various kelps especially of the genus Laminaria
	any of various coarse seaweeds
	brown algae seaweed with serrated edges
	a common rockweed used in preparing kelp and as manure
	a tart spicy quality
	the taste experience when a savoury condiment is taken into the mouth