tritocerebrum Syllabification: (tri·to·cer·e·brum)Pronunciation: /ˌtrītōsəˈrēbrəm, -ˈserə-/Definition of tritocerebrum noun (plural tritocerebra /-brə/) Entomology the third and hindmost segment of an insect’s brain. tritocerebrum in other Oxford dictionaries Definition of tritocerebrum in the British & World English dictionary