"In technical usage" means that this level of nitpicking isn't really accurate. When you say "they ran doom on a lamp" that isn't a piece of scientific literatu

"In technical usage" means that this level of nitpicking isn't really accurate. When you say "they ran doom on a lamp" that isn't a piece of scientific literature. It's just conversational English and as such using the common dictionary definition of the word lamp as opposed to a technical definition is entirely appropriate.