(mineralogy) A mineral that is a metadisilicate of calcium and sodium.

A surname.

plural of Rivadeneira

(rare) Characterised or marked by rivalry

Misspelling of ribavirin.

rivalry

plural of sibling rivalry

Competition or animosity between siblings in one family.

(economics) A scenario in which there is no competition between one person's consumption of a good or services as it does not prevent others from consuming it as well.