I feel completely in my element when talking to my friends in Spanish. But when I have to go to the hardware store, or auto parts store, I feel pretty ignorant of the language. Bujía is one of those words that makes me feel like I have a long way to go. Bujía is a spark plug.
Reading a couple of dictionaries, it seems like bujía can have something to do with a light bulb. I have not figured out what it could be, or how it is used. I don’t think it is a light in general, but a specific kind.