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Noun: h  eych
  1. The constant of proportionality relating the energy of a photon to its frequency; approximately 6.626 x 10^-34 joule-second
    - Planck's constant
  2. The 8th letter of the Roman alphabet
    - H
Noun: H  eych
  1. Material for starting a fire
    - kindling, tinder, touchwood, spunk [N. Amer], punk [N. Amer]
  2. A nonmetallic univalent element that is normally a colourless and odourless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
    - hydrogen, atomic number 1
  3. (thermodynamics) a thermodynamic quantity equal to the internal energy of a system plus the product of its volume and pressure
    "H is the amount of energy in a system capable of doing mechanical work";
    - heat content, total heat, enthalpy
  4. A unit of inductance in which an induced electromotive force of one volt is produced when the current is varied at the rate of one ampere per second
    - henry

Derived forms: hs, Hs

Type of: alphabetic character, chemical element, constant of proportionality, element, factor of proportionality, gas, igniter, ignitor, inductance unit, letter, letter of the alphabet, lighter, physical property

Part of: H2O, Latin alphabet, Roman alphabet, water

Encyclopedia: H