Definitions for underdoneˈʌn dərˈdʌn
Random House Webster's College Dictionary
not cooked enough.
Chiefly Brit. (of meat) rare.
Category: Cooking, British
Origin of underdone:
Kernerman English Learner's Dictionary
(of food) not fully cooked; = undercooked
The meat was underdone.
insufficiently cooked; undercooked