Added 9 October 2026 meteoroid noun Categories: NatureRare Words noun ! Definition from Wiktionary (CC BY-SA). More about meteoroid at Wordnik → Where our words come from → A relatively small (sand- to boulder-sized) fragment of debris in a star system that produces a meteor when it hits the atmosphere Related Words: meteormicrometeoroidmicroplanetoidmicrometeormicrometeoritemicroscopidminimooncometesimalmegacryometeormicroflaremicrostar Back to today's word