Lethologica: the inability to remember the word you want, even though it feels like it’s right there on the tip of your tongue. It’s basically the formal word for that maddening “ugh, what’s the word?” moment.
It comes from Greek roots meaning forgetfulness and word.
Example:
“I had a total bout of lethologica and couldn’t remember the word umbrella.”
Great word, honestly. Tiny tragedy in one package.