cheloid vs cicatrix

cheloid and cicatrix both are nouns.

Word	Noun	Adjective	Verb	Adverb
cheloid	Yes	No	No	No
cicatrix	Yes	No	No	No

As nouns, cicatrix is a hypernym of cheloid; that is, cicatrix is a word with a broader meaning than cheloid:

cheloid: raised pinkish scar tissue at the site of an injury; results from excessive tissue repair
cicatrix: a mark left (usually on the skin) by the healing of injured tissue

Other hypernyms of cheloid include cicatrice, scar.

cheloid (noun)	cicatrix (noun)
raised pinkish scar tissue at the site of an injury; results from excessive tissue repair	a mark left (usually on the skin) by the healing of injured tissue