Words you don't know for things you do know.
It was rather a coincidence that I once passed a word that I didn't know at all, and when I looked it up, I noticed that I knew the explanation of it.
Then I wrote a blog about it once.
Sometimes we simply do not name it.
Recently, I came across such a word again.
I decided to write down and collect these kinds of words.
Here they come.

Gnurr
You know it: after a few washes you will notice that dust collects in the tips of your pockets.
Or in the cover of your trouser legs at the bottom. That substance is called gnurr.
(You do not pronounce the 'g', the 'u' is short.)

Quidnunc
A quidnunc is a person who interferes with everything, who likes to take control,
even if in fact it's not his/her business. The word is also used for a small exterior mirror, next to a window.
A “cheat mirror, “say.