What is of or pertaining to, or in the form of, a helix; spiral; as, a helical staircase; a helical spring. -- Hel"i*cal*ly, adv called?

helical — Of or pertaining to, or in the form of, a helix; spiral; as, a helical staircase; a helical spring. -- Hel"i*cal*ly, adv. (Webster's 1913.)

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