We don't have synonyms for triodes yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are triode, triones and trioses.
(n) :
A thermionic valve containing an anode, a cathode, and a control grid; small changes to the charge on the grid control the flow from cathode to anode, which makes amplification possible.
(n) :
A thermionic valve containing an anode, a cathode, and a control grid; small changes to the charge on the grid control the flow from cathode to anode, which makes amplification possible.