pill vs onus

pill and onus both are nouns.

Word	Noun	Adjective	Verb	Adverb
pill	Yes	No	No	No
onus	Yes	No	No	No

As nouns, onus is a hypernym of pill; that is, onus is a word with a broader meaning than pill:

Other hypernyms of pill include burden, encumbrance, incumbrance, load.

pill (noun)	onus (noun)
a dose of medicine in the form of a small pellet	an onerous or difficult concern
something that resembles a tablet of medicine in shape or size
a contraceptive in the form of a pill containing estrogen and progestin to inhibit ovulation and so prevent conception
something unpleasant or offensive that must be tolerated or endured
a unpleasant or tiresome person