means DON'T, nothing else. Even a blind person would notice whether its a missspelling or not and still see that it's Don't / Do Not
i dnt know
DNT: Designated Nap Time
A specified time period which allows a generally productive person to sleep during the day.
DNT is typically reserved for people (such as college students) who have freedom in their schedule, regularly stay up past 2am, but have to get up before 8 am. (DNT's usually last from 30 minutes to an hour, but some have been known to require 2 hours or more).
"We'll go eat lunch as long as I'm back by 2:00 for my DNT."