from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Mathematics A three-dimensional curve that lies on a cylinder or cone, so that its angle to a plane perpendicular to the axis is constant.
- n. A spiral form or structure.
- n. Anatomy The folded rim of skin and cartilage around most of the outer ear.
- n. Architecture A volute on a Corinthian or Ionic capital.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A curve on the surface of a cylinder or cone such that its angle to a plane perpendicular to the axis is constant; the three-dimensional curve seen in a screw or a spiral staircase.
- n. A small volute under the abacus of a Corinthian capital.
- n. The incurved rim of the external ear.
from the GNU version of the Collaborative International Dictionary of English
- n. A nonplane curve whose tangents are all equally inclined to a given plane. The common helix is the curve formed by the thread of the ordinary screw. It is distinguished from the spiral, all the convolutions of which are in the plane.
- n. A caulicule or little volute under the abacus of the Corinthian capital.
- n. The incurved margin or rim of the external ear. See Illust. of Ear.
- n. A genus of land snails, including a large number of species.
from The Century Dictionary and Cyclopedia
- n. A spiral line, as of wire in a coil; a winding, or something that is spiral; a circumvolution; specifically, in geometry, the curve assumed by a right line drawn on a plane when that plane is wrapped round a cylindrical surface of any kind, especially a right cylinder, as the curve of a screw-thread; also, a curve on any developable surface which becomes a right “line when the surface is developed into a plane, as a conical helix.
- n. In architecture, any spiral, particularly a small volute or twist under the abacus of the Corinthian capital; also, a volute of the Ionic capital.
- n. In electricity, a coil of wire, as that surrounding the core of an electromagnet.
- n. In anatomy: The prominent curved fold which forms most of the rim or margin of the outer ear. See second cut under ear.
- n. The cochlea of the inner ear.
- n. [capitalized] [NL.] In conchology, the representative genus of Helicidæ and Helicinæ.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a curve that lies on the surface of a cylinder or cone and cuts the element at a constant angle
- n. a structure consisting of something wound in a continuous series of loops
- n. type genus of the family Helicidae
Even the double helix is a sort of spell-checker, for editorial enzymes can compare one DNA base with its opposite and undamaged number to check that it fits.
The double helix is then untwisted and forms two single strands which can be duplicated with the help of the enzyme DNA polymerase.
At these locations the DNA-helix is severed: the pages of the book are separated.
In that case the far end of the helix was the Ice Age, and we are now moving towards the center of the helix in which case everything warms up.
– 'Zippers' are conceptually at work in the DNA double helix, which is "unzipped" for replication and transcription
I prefer a Quad helix, which is kind of spring loaded and the parent doesn't have to do anything.
A helix is a three-dimensional spiral, like the shape of a spring or the railing on a spiral staircase.
Each twist of the helix is a mere 70 billionths of a meter in length and approximately 10 in diameter.
A third subunit, H, without active groups and located on the membrane inner surface, is anchored to the membrane by a protein helix.
The screw is made by rolling a flat steel strip between rollers set at an inclination to each other to squeeze one edge of the strip and hence cause it to curl into a helix, which is then welded to an inner cylindrical pipe.