I am all the time busy, whether it is while doing the work that brings in money to my household or if I am idle looking at the clouds as I walk. This definition of busy is not what you get to hear very often, but as long as I am doing something, even if it is not doing anything, I will define it as busy.
Now, the elevator is a place where I have heard the word busy many times. "Hi, how are you?" - "Ah, busy" followed by a sigh. That busy is different. What I really think it means is "Ah, overwhelmed."
But I can not even dream of listening to my high-achiever co-workers to declare that they are overwhelmed. Busy can be carried with a badge of honor. Overwhelmed, I think, states that things are not working. Thus, overwhelm does not feed into the story of work hard, and until exhaustion.
I could be busy, but not overwhelmed. Acknowledging that possibility may help me to realize when to stop and take a break in the future.
Thoughts while reading Four thousand weeks: time management for mortals.