helicity

American  

[hee-lis-i-tee, hi-] / hiˈlɪs ɪ ti, hɪ- /

noun

• helicities
  plural

1. Physics. the projection of a particle's spin along the direction of its momentum.

2. Biochemistry. (especially of DNA) the character or characteristic of having the form of a helix.

3. Meteorology. the helical rotation in a storm's updraft, the potential of which is a proportional measure of speed, direction, and inflow, factors that are especially critical in the forecasting and mapping of tornadoes.

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helicity British  

/ hɪˈlɪsɪtɪ /

noun

1. physics the projection of the spin of an elementary particle on the direction of propagation

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helicity Scientific  

/ hə-lĭs′ĭ-tē,hē′ /

1. The projection of a particle's spin vector in the direction of its momentum vector, being positive if it points in the same direction, and negative if it points in the opposite direction. Helicity is in effect the handedness, or chirality, of the spin of a particle.

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Other Word Forms

Derived Forms

• superhelicity
  noun

Inflected Forms

Nouns

• helicities
  plural

Etymology

Origin of helicity

C20: from _helix + _-ity

Example Sentences

See Examples For:

helicity

These antennas absorb light with a particular color and helicity, then emit that light in a specific direction.

From Science Daily ● Aug. 18, 2026

By changing the helicity, or twist, of the circularly polarized pulses, the team could stabilize either the clockwise or anti-clockwise arrangement of electric dipoles.

From Science Daily ● Nov. 21, 2025

Many allowed decay modes, which typically involve charmed hadrons and other particles, have angular momentum configurations that are not helicity suppressed.

From Nature ● May 12, 2015