# Axis of symmetry

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Jump to navigationJump to searchAn imaginary line in a crystal, crystal structure, or crystal lattice, about which it may be rotated to an identical configuration. If identity occurs once during a complete rotation of 360 degrees , the axis is a monad, twice a diad, thrice a triad, four times a tetrad, or six times a hexad. Syn: symmetry axis

Source: Dictionary of Mining, Mineral, and Related Terms