Seems like you have your best shot if you make it seem like a lack of knowledge on a given topic is really safe. “Is this something you’ve nerded out on before, or not yet? Oh you have - cool, it’s pretty esoteric. Do you know enough to summarize it in a sentence or a few? If not I like to try to give my own high level before diving in.”
Something open ended in there gives you a chance to validate whether the ‘I know what that is’ was ego or truth.