lysine vs essential amino acid

lysine and essential amino acid both are nouns.

Word	Noun	Adjective	Verb	Adverb
lysine	Yes	No	No	No
essential amino acid	Yes	No	No	No

As nouns, essential amino acid is a hypernym of lysine; that is, essential amino acid is a word with a broader meaning than lysine:

lysine: an essential amino acid found in proteins; occurs especially in gelatin and casein
essential amino acid: an amino acid that is required by animals but that they cannot synthesize; must be supplied in the diet

lysine (noun)	essential amino acid (noun)
an essential amino acid found in proteins; occurs especially in gelatin and casein	an amino acid that is required by animals but that they cannot synthesize; must be supplied in the diet