cataplasm vs medical dressing

cataplasm and medical dressing both are nouns.

Word	Noun	Adjective	Verb	Adverb
cataplasm	Yes	No	No	No
medical dressing	Yes	No	No	No

As nouns, medical dressing is a hypernym of cataplasm; that is, medical dressing is a word with a broader meaning than cataplasm:

cataplasm: a medical dressing consisting of a soft heated mass of meal or clay that is spread on a cloth and applied to the skin to treat inflamed areas or improve circulation etc.
medical dressing: a cloth covering for a wound or sore

Other hypernyms of cataplasm include dressing.

cataplasm (noun)	medical dressing (noun)
a medical dressing consisting of a soft heated mass of meal or clay that is spread on a cloth and applied to the skin to treat inflamed areas or improve circulation etc.	a cloth covering for a wound or sore