Definition of "tetrode" [tetrode]

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

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "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."
• "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."
• ""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.""