It's the only word we've heard that refers to the condition, and we've never heard it applied to anything else, so I actually think it is quite literally an Old Tongue word that means "the black dots that float in front of the eyes of someone addicted to the True Power".

It would be somewhat like asking what saidin and saidar are. We know that 'saidar' in the real world is a Scandinavian word meaning magic, but in RJ's world it appears those are the Old Tongue words referring to the two halves of the One Power with no deviation or alternative.