from
The Collaborative International Dictionary of English v.0.48
Vexillar \Vex"il*lar\, Vexillary \Vex"il*la*ry\, [Cf. F.
vexillaire, L. vexillarius a standard bearer.]
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1. Of or pertaining to an ensign or standard.
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2. (Bot.) Of or pertaining to the vexillum, or upper petal of
papilionaceous flowers.
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{Vexilary aestivation} (Bot.), a mode of aestivation in which
one large upper petal folds over, and covers, the other
smaller petals, as in most papilionaceous plants.
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