[stephen_g]

Yes, it’s not hard to use “it’s a bit like X” or it’s “kind of like Y” when giving a simplified explanation or using an analogy. Even young kids can understand that. And I’ve never understood why people would make something up if they don’t know something - in fact, it’s a good learning opportunity in two ways - first, it’s good to show you’re not embarrassed or ashamed by not knowing something, and secondly it’s a good exercise to encourage the child to try and think of ideas together of what might be the explanation.

(That said, if you are good at switching demeanour to make it obvious to them that you're not serious, kids do often enjoy the absurd and ridiculous, so it can be fun to 'lie' to kids in that way by offering increasingly absurd explanations. But care must be taken to ensure they know you're not actually trying to mislead them!)