headache powder vs Empirin

headache powder and Empirin both are nouns.

Word	Noun	Adjective	Verb	Adverb
headache powder	Yes	No	No	No
Empirin	Yes	No	No	No

As nouns, Empirin is a hypernym of headache powder; that is, Empirin is a word with a broader meaning than headache powder:

headache powder: a powdered form of aspirin
Empirin: the acetylated derivative of salicylic acid; used as an analgesic anti-inflammatory drug (trade names Bayer, Empirin, and St. Joseph) usually taken in tablet form; used as an antipyretic; slows clotting of the blood by poisoning platelets

Other hypernyms of headache powder include acetylsalicylic acid, aspirin, Bayer, St. Joseph, powder.

headache powder (noun)	Empirin (noun)
a powdered form of aspirin	the acetylated derivative of salicylic acid; used as an analgesic anti-inflammatory drug (trade names Bayer, Empirin, and St. Joseph) usually taken in tablet form; used as an antipyretic; slows clotting of the blood by poisoning platelets