bilinear Syllabification: (bi·lin·e·ar)Pronunciation: /bīˈlinēər/Definition of bilinear adjective Mathematics 1 rare of, relating to, or contained by two straight lines. 2of, relating to, or denoting a function of two variables that is linear and homogeneous in both independently. bilinear in other Oxford dictionaries Definition of bilinear in the British & World English dictionary