I call it "Kindergarten speak". People at the highest level of technical expertise sometimes have it, where they can patiently, and in understandable terms, explain to the most junior (but interested) party so the stuff sticks.

Others, while extremely nice and helpful, just don't "get" that their advanced jargon or, in my workplace, advanced mathematical language/notation, however elegant for themselves, is a huge hindrance for those not as versed in the art.

So if I, personally, say someone can explain something in kindergarten speak, that's the highest compliment. The more advanced lingo/notation stuff can come later, once the explainee has the big picture.