noun
Refers to a curve winding around a central point or axis, including both 2D spirals and 3D helices. Common in geometry, biology, and everyday description.
DNAは二重らせん構造をしている。
DNA has a double helix structure.
階段が螺旋状に上
The stairs continue upward in a spiral.
noun
Specifically refers to a screw thread or a screw-shaped object. Often used in mechanical contexts; compare with ねじ for a more general 'screw' as a fastener.
See also: ねじ
この部品には細かい螺旋が切ってある。
This part has a fine screw thread cut into it.