I'm not so certain that the issue is the definition of the term normal, so much as it is the value (positive or negative) or association (healthy vs. unhealthy) the term implies in a medical or social context.
One of the most common reasons for blurry vision while wearing contacts is that your eyes are dry. Some people have a medical condition that causes dry eyes, called dry eye syndrome, but others' eyes are irritated by the contacts themselves.
1 Remove contact lenses before using Clear Eyes Extra Relief Drops. 2  Do not use Clear Eyes Extra Relief Drops if it becomes cloudy or changes color.  Contact your doctor if you experience changes in vision, eye pain, irritation, soreness, or continued redness, or if your condition does not improve after 3 days.