The word "gelatinate" refers to the process of forming a gel or becoming gel-like. As such, some antonyms for this term could include words like solidify, harden, crystallize, coagulate, or congeal. These are all processes that involve the opposite of creating a gel-like substance, instead transforming a liquid or soft material into a more solid form. Other antonyms for gelatinate might include words like liquefy, melt, dissolve, or thin out, which describe processes of creating a fluid or less dense material. By understanding these antonyms, we can better understand the range of physical transformations that can occur within a substance.