Tonocard vs antiarrhythmic

Tonocard and antiarrhythmic both are nouns.

Word	Noun	Adjective	Verb	Adverb
Tonocard	Yes	No	No	No
antiarrhythmic	Yes	No	No	No

As nouns, antiarrhythmic is a hypernym of Tonocard; that is, antiarrhythmic is a word with a broader meaning than Tonocard:

Tonocard: antiarrhythmic drug (trade name Tonocard) used to treat ventricular arrhythmias when less dangerous drugs have failed
antiarrhythmic: a drug used to treat an abnormal heart rhythm

Other hypernyms of Tonocard include antiarrhythmic drug, antiarrhythmic medication.

Tonocard (noun)	antiarrhythmic (noun)
antiarrhythmic drug (trade name Tonocard) used to treat ventricular arrhythmias when less dangerous drugs have failed	a drug used to treat an abnormal heart rhythm