If you're not a Junior and that's all you have to say without even attempting to approach the actual question, you would be raising a red flag with me. Maybe there are better ways to phrase that counter-question, but this one in particular made me twitch.

In my experience, outlining one or a few things you call interfaces would be a much better display of both knowledge and attitude: GUI, API, interface keyword or concept in some programming language, etc. Even better, add a quick description of what they all have in common ("broadly speaking, a way to access a set of functionality" or something like that).

And THEN you may ask "would you like me to elaborate on one meaning in particular?"

Possible alternative phrasing - "That might depend on the context. Is there a particular context you had in mind or did you want me to answer in a very broad sense?"