I was only recently educated on the existence of Apple's Dictionary. My Mac education has been a slow one. It's embarrassing but I still don't know how to use spaces (don't judge me. Kellie I'm talking to you).
Apple's Dictionary is simple but classically lovely. How can I not be happy when I see the serifs and italics, and it even helps me choose the right word! So clever.
This wins any day over an online dictionary website with flashing ads everywhere (Merriam-Webster, I talking to you).