“principal plane”

We have one entry that includes the term principal plane.

principal plane of symmetry

: a plane of symmetry in a crystal that includes two or more axes of symmetry

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Name That Flower

  • any of a genus helianthus especially h annuus of new world composite plants with large yellow rayed flower heads bearing edible seeds that yield an edible oil
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Commonly Confused Words Quiz Vol. 3 Do you have a (flare/flair) for choosing the righ...