I also have this problem of saying the wrong word. Not only out loud but also if I'm thinking to myself.
My symptoms begun about 10 months ago, but for the last three years have also had the problem of not being able to think of a word that I want to say, my mind goes completely blank. Literally.
My wrong words are connected to the words that I want to say and I always say the same wrong word.
Example - I always call the Hover lawnmower a hoover
I always call the rotary washing line an umbrella (same shape)
and always call the woodpecker that comes into our garden a cuckoo.
This seems weird to me as although I am saying the wrong word, it's always the same wrong word, I did notice that when it first started it was worse around the time of my menstruation cycle. I'm 48.
I also have vertigo for which I am prescribed Nasonex. I am fine with reading / writing / spelling and numbers. Is this the same situation as others are experiencing ???