「まずい」 (Mazui) is an i-adjective meaning 'bad tasting' or 'distasteful'. It's used to describe food or drink that has an unpleasant flavor. While primarily about taste, it can also informally mean 'bad' or 'undesirable' in other contexts.

「まずい」は「bad tasting, distasteful」という意味のい形容詞です。食べ物や飲み物の味が悪いことを表します。