lymphoid tissue vs node

lymphoid tissue and node both are nouns.

Word	Noun	Adjective	Verb	Adverb
lymphoid tissue	Yes	No	No	No
node	Yes	No	No	No

As nouns, node is a hyponym of lymphoid tissue; that is, node is a word with a more specific, narrower meaning than lymphoid tissue:

lymphoid tissue (noun)	node (noun)
tissue making up the lymphatic system	(computer science) any computer that is hooked up to a computer network
	any bulge or swelling of an anatomical structure or part
	the source of lymph and lymphocytes
	(astronomy) a point where an orbit crosses a plane
	(physics) the point of minimum displacement in a periodic system
	(botany) the small swelling that is the part of a plant stem from which one or more leaves emerge
	any thickened enlargement
	a connecting point at which several lines come together