The word "rare" is an adjective that describessomethinguncommonornotoftenfound. It can refer to objects, qualities, orcooking styles, especially when discussing how meat is prepared.
Adjective
(of meat) cooked a shorttime; stillredinside
rareroast beef
markedby an uncommonquality; especiallysuperlativeorextreme of itskind
what is so rareas a day in June-J.R.Lowell
a rareskill
an uncommonsense of humor
she waskind to an uncommondegree
havinglow density
raregasses
lightheaded from the rarefiedmountainair
notwidely distributed
rareherbs
rarepatches of green in the desert
recurringonlyat long intervals
a rareappearance
totaleclipsesarerareevents
notwidelyknown; especiallyvalued for itsuncommonness