What is a simple pistil or single-celled ovary or seed vessel, or one of the parts of a compound pistil, ovary, or seed vessel. See Illust of Carpaphore called?

carpel — A simple pistil or single-celled ovary or seed vessel, or one of the parts of a compound pistil, ovary, or seed vessel. See Illust of Carpaphore. (Webster's 1913.)

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