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{%type%} Definitions

WordNet 3.0Copyright Princeton University


Short "hint"

A polyhedron of four faces. (plural)

Usage examples (37)
  • In sheet silicates, each silicate tetrahedron is joined at 3 corners to other tetrahedra in sheet form.
  • Five points form the vertices of two regular tetrahedra, joined on a common face situated in the horizontal plane.
  • The crystalline structure common to amphibole minerals consists of two ribbons of silicate tetrahedra placed back to back.
  • Each of the 3 corners “shares” an oxygen atom with other tetrahedra, giving a ratio in the formula of 1 Si to 2.5 O, or Si2O5. for more
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