Word confusion

I needed to vacuum yesterday so I told Micah that I was going to do that. He ran to the island cabinets and said "I'll get the lowercase vacuum."  And got the hand held DustBuster. (Lowercase vacuum?????- what?). I realized after a moment that as we talk about letters I usually try to say capital and lowercase. Other times though, and in one game we have, the letters are referred to as big and little. 

So apparently little and lowercase are synonyms for Micah. I didn't try to explain, I just enjoyed the thoughtful cuteness.