1. Yielding or containing plenty; affording ample supply: a copious harvest. See Synonyms at plentiful.
2. Large in quantity; abundant: copious rainfall.
3. Abounding in matter, thoughts, or words; wordy: "I found our speech copious without order, and energetic without rules" (Samuel Johnson).
[Middle English, from Latin cōpiōsus, from cōpia, abundance; see op- in the Appendix of Indo-European roots.]
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