Lardaceous is an adjective that is used to describe something that is fatty or greasy in nature. Some potential antonyms for this word could include words like lean, light, or thin. These words all convey a sense of being devoid of excess fat or heaviness, which is the polar opposite of the heavy, oily connotations that come with lardaceous. Additionally, words like wiry, sinewy, or bony could be considered antonyms to lardaceous, as they all evoke a sense of being skinny or devoid of any fat. Ultimately, antonyms for lardaceous will depend on the context and the particular contrast that is being drawn with this adjective.