[dahy-nuh-tron] 
| a tetrode, once frequently used as an oscillator in radio, in which an increase in the plate voltage results in a decrease in the plate current because of emission of electrons from the plate. |
| dy·na·tron (dī'nə-trŏn') n. A tetrode with grid and plate potentials so arranged that plate current decreases when plate potential increases. [Greek dunamis, power; see dynamic + -tron.] |
nəˌtrɒn