hyperboloid Syllabification: (hy·per·bo·loid)Pronunciation: /hīˈpərbəˌloid/Definition of hyperboloid noun a solid or surface having plane sections that are hyperbolas, ellipses, or circles. Derivatives hyperboloidalPronunciation: /hīˌpərbəˈloidl/ adjective hyperboloid in other Oxford dictionaries Definition of hyperboloid in the British & World English dictionary