deoxyribose \deoxyribose\ n. a pentose ({C5H10O4}) in which one of the hydroxyl groups of ribose has been replaced by a hydrogen. In deoxyribonucleic acids, the deoxyribose is {D-2-deoxyribose}, in which the hydroxyl at the 2 position of ribose is the one which is replaced by hydrogen. [PJC]