As verbs the difference between rared and rare
is that
rared is (
rare) while
rare is (us|intransitive) to rear, rise up, start backwards.
As an adjective rare is
(cooking|particularly meats) cooked very lightly, so the meat is still red (in the case of steak or beef in the general sense) or
rare can be very uncommon; scarce or
rare can be (obsolete) early.