Rolaids vs alkaliser

Rolaids and alkaliser both are nouns.

Word	Noun	Adjective	Verb	Adverb
Rolaids	Yes	No	No	No
alkaliser	Yes	No	No	No

As nouns, alkaliser is a hypernym of Rolaids; that is, alkaliser is a word with a broader meaning than Rolaids:

Rolaids: an antacid
alkaliser: an agent that counteracts or neutralizes acidity (especially in the stomach)

Other hypernyms of Rolaids include alkalizer, antacid, antiacid, gastric antacid.

Rolaids (noun)	alkaliser (noun)
an antacid	an agent that counteracts or neutralizes acidity (especially in the stomach)