One who is in pursuit of the same object as another; one striving to reach or obtain something which another is attempting to obtain, and which one only can posses; a competitor; as, rivals in love; rivals for a crown.

Having the same pretensions or claims; standing in competition for superiority; as, rival lovers; rival claims or pretensions.

To stand in competition with; to strive to gain some object in opposition to; as, to rival one in love.

be equal to in quality or ability; "Nothing can rival cotton for durability"; "Your performance doesn't even touch that of your colleagues"; "Her persistence and ambition only matches that of her parents"

Rivals! (Japanese: ライバル！ Raibaru) is the second opening theme song of the Pocket Monsters series.

A person having a common right or privilege with another; a partner.

a good thing to have, but only if it's up to the task

To be in rivalry.