n. A soft, semisolid food substance with a resilient consistency, made by the setting of a liquid containing pectin or gelatin or by the addition of gelatin to a liquid, especially such a substance made of fruit juice containing pectin boiled with sugar.n. Something, such as a petroleum ointment, having the consistency of a soft, semisolid food substance.n. A shapeless, pulpy mass: The hero's laser zapped the monster, turning it to jelly. n. Something, such as a body part, that has suddenly become limp or enervated: Her knees turned to jelly when she learned she won first prize. n. A jellyfish.v. To cause to have the consistency of jelly.verb-intransitive. To acquire the consistency of jelly. See Synonyms at coagulate.