Osmitrol vs water pill

Osmitrol and water pill both are nouns.

Word	Noun	Adjective	Verb	Adverb
Osmitrol	Yes	No	No	No
water pill	Yes	No	No	No

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

Osmitrol: a diuretic (trade name Osmitrol) used to promote the excretion of urine
water pill: any substance that tends to increase the flow of urine, which causes the body to get rid of excess water

Other hypernyms of Osmitrol include diuretic, diuretic drug.

Osmitrol (noun)	water pill (noun)
a diuretic (trade name Osmitrol) used to promote the excretion of urine	any substance that tends to increase the flow of urine, which causes the body to get rid of excess water