ratatouille Syllabification: (ra·ta·touille)Pronunciation: /ˌratəˈto͞o-ē, ˌräˌtä-/Definition of ratatouille noun a vegetable dish consisting of onions, zucchini, tomatoes, eggplant, and peppers, fried and stewed in oil and sometimes served cold. Origin:a French dialect wordSpell ratatouille (a French word) with -oui- in the middle; the ending is -lle.ratatouille in other Oxford dictionaries Definition of ratatouille in the British & World English dictionary