jellEnglishOxford New American Dictionaryjell /jel, dʒɛl / ▸ verb (jells, jelling, jelled) [no object] mainly North American 1 (of a liquid or semiliquid substance) set or become more solid: she works at it all day but can't get the jelly to jell chicken or fish stock will jell when chilled. 2 (of a project or idea) take a definite form or begin to work well: he decided to do a different film that would jell at the box office. ▪ (of people) work well together: we went out there and tried to win, but we just didn't jell. – ORIGIN mid 18th century : back-formation from jelly1. See also gel1.