Aug 15, 2025 copious ˈkō-pē-əs 3 syllables rare ‹ adjective. yielding something abundantly a copious harvestcopious springs adjective. plentiful in number copious references to other writers… Shakespeare, whose soul was so copious … adjective. full of thought, information, or matter a copious talkercopious weeping › Origin Middle English, from Latin copiosus, from copia abundance, from co- + ops wealth. Synonyms abundant