Triode

Part of speech: noun

Pronunciation: /ˈtɹaɪ.əʊd/

Definitions

1. A three-electrode electronic device utilized for amplifying signals by controlling current flow through its components
2. An electronic component featuring three terminals that facilitates the modulation and amplification of electrical signals
3. A vacuum tube with three electrodes designed to amplify electrical signals by controlling electron flow

Etymology: The triode is a case where the name tells you the whole design. "Tri-" is the familiar Greek-derived prefix for three, and "-ode" comes from Greek "hodos," meaning a way or path, which in electronics is used to mean the path that electrons travel. Put together, the word names a vacuum tube with three electrodes: a cathode that emits electrons, a plate that collects them, and a control grid placed between the two. That grid is what made the device useful. Earlier two-electrode tubes could rectify current but could not amplify a signal. By inserting a third electrode whose small voltage governs the flow of electrons across the gap, engineers could make a weak signal control a much larger current, which is the essence of amplification. The "-ode" element is shared with older electronic terms like diode, so the triode was named as the next member of that family.

Synonyms: valve, tube