bilevel noun 3adjective 1forms 1 noun3 •A house with two adjacent levels that are less than a story apart.They live in a little bilevel on the edge of town. •A women's hairstyle similar to the mullet.MULLET / Now this is what we call “business in the front, party in the back”! A male haircut derived from the 1980s female-oriented bi-level […] — 2005 •A binary image, one that has only two possible values for each pixel (usually black and white). adjective1 •Having two levels.We developed a bilevel approach to the problem. formsbilevels