ursine UK /ˈɜː.saɪn/US /ˈɝsaɪn/adjective 3noun 1forms 3 adjective3 •Of, pertaining to, or characteristic of bears.The British chief having undergone the ursine embrace of the Seikh monarch, the whole cavalcade proceeded towards the town. — 1832 •Of, pertaining to, or characteristic of the bear subfamily Ursinae. •Covered in stiff bristles. noun1 •A bear. formsursines · more ursine · most ursine