| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
| a gadget; dingus; thingumbob. |
| photodiode (fō'tō-dī'ōd') Pronunciation Key
A diode that exhibits sensitivity to light, either by varying its electrical resistance like a photoresistor, or generating a electric potential in the manner of a photoelectric cell. See more at photoelectric. |