The Collaborative International Dictionary of English v.0.48:

Rondure \Ron"dure\, n. [Cf. F. rondeur roundness.]
   1. A round; a circle. [Obs.] --Shak.
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   2. Roundness; plumpness. [R.]
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            High-kirtled for the chase, and what was shown
            Of maiden rondure, like the rose half-blown.
                                                  --Lowell.
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