cruel: [13] Aptly, cruelty and crudeness are closely linked etymologically. Cruel comes via Old French cruel from Latin crūdēlis, a relative of Latin crūdus (which actually meant ‘cruel’ as well as ‘raw’ and ‘bloody’). Both come ultimately from an Indo-European base which also produced English raw, Greek kréas ‘flesh’ (whence English creosote and pancreas), and Old Slavic kruvi ‘blood’. (Crude is a 14thcentury borrowing direct from Latin.) => creosote, crude, pancreas, raw
cruel (adj.)
early 13c., from Old French cruel (12c.), earlier crudel, from Latin crudelis "rude, unfeeling; cruel, hard-hearted," related to crudus "rough, raw, bloody" (see crude). Related: Cruelly. Latin medial -d- began to disappear 10c. in French: compare chance/cadentia, cheoir/cadere, joyeux/gaudiosus, juif/judaeus, moyen/medianus, obéir/obedire, séance/sedentia.