helix

[ hee-liks ]

noun

, plural hel·i·ces [hel, -, uh, -seez], he·lix·es.

1. a spiral.
2. Geometry. the curve formed by a straight line drawn on a plane when that plane is wrapped around a cylindrical surface of any kind, especially a right circular cylinder, as the curve of a screw. Equation: x = a sinθ, y = a cosθ, z = b θ.
3. Architecture.
   1. a spiral ornament.
   2. (in a Corinthian capital) either of two scrolls issuing from a cauliculus. Compare Corinthian ( def 2 ).
4. Anatomy. the curved fold forming most of the rim of the external ear.
5. Biochemistry. alpha helix.

helix

/ ˈhiːlɪks /

noun

1. a curve that lies on a cylinder or cone, at a constant angle to the line segments making up the surface; spiral
2. a spiral shape or form
3. the incurving fold that forms the margin of the external ear
4. another name for volute
5. any terrestrial gastropod mollusc of the genus Helix, which includes the garden snail ( H. aspersa )

helix

/ hē′lĭks /

1. A three-dimensional spiral curve. In mathematical terms, a helix can be described as a curve turning about an axis on the surface of a cylinder or cone while rising at a constant upward angle from a base.
2. Something, such as a strand of DNA, having a spiral shape.

helix

1. In geometry , a three-dimensional spiral shape, resembling a spring.

Word History and Origins

Origin of helix¹

1555–65; < Latin: a spiral, a kind of ivy < Greek hélix anything twisted; compare helíssein to turn, twist, roll

Word History and Origins

Origin of helix¹

C16: from Latin, from Greek: spiral; probably related to Greek helissein to twist

Example Sentences

Hedéra Hélix, Irish Ivy, is a valuable evergreen for covering naked walls, or any other unsightly object.

From Project Gutenberg

Related Words

• arc
• arch
• contour
• loop
• trajectory