I actually know someone who has very mild disnomia and one of the words he always forgets is disnomia
For years I've said I have some aphasia. Now I learned that I probably have the mild form called disnomia.
I don't even notice when I've called someone, or referred to someone, by the wrong name. I often say the wrong color. The joke in my house is that when I say "the green one" I simply mean it has a color not that it's actually green.