words I didn't know

Today I learned that 'dendrogram' is a word. It's a kind of diagram with a tree-like structure, and programmers and statisticians each seem to think they're the only ones who use them.

Then I learned that you can eat offal. Apparently it doesn't just refer to animal guts you'd want to chuck, but other animal guts, too. I did not know that. I'm having a hard time getting over the word 'offal.'