Dementia here I come

Anybody else have a word go missing from their vocabulary? I'm talking a simple, everyday word, one you've read and said hundreds of times just drop out and leave you half angry and half terrified?

Its happened to me. In fact, recently, I was trying to relate a story about a time when this happened, and the SAME WORD hat had given me such distress the first time disappeared as I was trying to talk about it.

Sighs. Dementia here I come ...