from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A four-element electron tube containing an anode, cathode, control grid, and additional electrode.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A thermionic valve similar to a triode with the addition of a screen grid to protect the control grid
  • n. A dynatron

from The Century Dictionary and Cyclopedia

  • n. Among the sponge-spicules, one with four equal rays in the same plane.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a thermionic tube having four electrodes


Sorry, no etymologies found.


  • Graphical Symbol in full simplified diode, indirectly heated duodiode, indirectly heated or triode, indirectly heated or duotriode with separated cathodes, indirectly heated, heating filament with central tapping, internal screening of the system tetrode pentode, suppressor grid connected with cathode triode - pentode triode - heptode (according to the circuit, the systems may be drawn left-and-right reversed) 1.10.

    1. Selected Graphical Symbols of Electrotechnology

  • To get to distance from acceleration, the Rocket had to integrate twice-needed a moving coil, transformers, electrolytic cell, bridge of diodes, one tetrode (an extra grid to screen away capacitive coupling inside the tube), an elaborate dance of design precautions to get to what human eyes saw first of all-the distance along the flight path.

    Gravity's Rainbow

  • "For recording, we used chronically implanted multi-tetrode arrays - a technique that offered us the chance to monitor many neurons at extremely high recording quality." - latest science and technology news stories

  • We thank Ruud Joosten for help with construction of the tetrode arrays and with surgeries,

    PLoS Biology: New Articles


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