bronto-comb. form of Gr. βροντή thunder, as in brontogram|ˈbrɒntəʊgræm|, the record made by a brontometer or brontograph; ˈbrontograph, a recording brontometer; also, a chart of the phenomena recorded by that instrument; brontoˈlogicala., pertaining to brontology; bronˈtometer, an instrument for recording the phenomena associated with thunderstorms; brontoˈphobia, intense dread of thunder and thunderstorms.1888Symons's Monthly Meteorol.Mag. June 71 Our German friends..were clearly the first as to thunder-storms, or rather Brontological research.Ibid. May 50 Messrs. Richard Frères, of Paris, are constructing for Mr. Symons a very complicated apparatus (Brontometer)..for recording the details of thunderstorms.1905W. G. Holmes Justinian & Theodora I. iii. 298 He was affected with brontophobia in his later years.
bronto-/ˈbrɒntəʊ/combining form of Greek brontē thunder: see -o-.