The plural of helix is helices or helixes.
A helix is a three-dimensional curve or spiral shape characterized by a constant curvature. It resembles a coiled spring or a corkscrew and can be found in various natural and man-made structures.
In biology, the DNA double helix is a famous example of a helical structure.
In mathematics and physics, helices are studied for their properties and applications in different fields. The term 'helix' is used to describe a specific geometric shape that exhibits a consistent curvature and rotational symmetry.
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Plural:
The graph shows the occurances of the plural of helix in written English since 1800 using Google's Ngram Viewer.
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