: a crystal consisting of two pyramids base to base, the one geometrically a mirror image of the other with respect to the horizontal plane of symmetry
dipyramids occur in the tetragonal, hexagonal, and orthorhombic systems and may have corresponding orthorhombic, tetragonal, ditetragonal, hexagonal, or dihexagonal symmetry

Word History


di- + pyramid

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

Dictionary Entries Near dipyramid

Cite this Entry

“Dipyramid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dipyramid. Accessed 19 May. 2024.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!