Where does yut come from?
While the United States Marine Corps was formed in 1775, it's not clear when, exactly, the Marines started saying yut.
Since at least the 20th century, yut has been a motivational exclamation used to show enthusiasm. It may be a variant on yes or the drill command, ten-hut. The term is sometimes used in place of another popular Marine-ism, Oorah!, originating as a battle cry.
The Marine slang is not to be confused with the traditional Korean table game Yut (Nori), usually played with special yut sticks and associated with the Korean New Year.
Who uses yut?
In the service, Marines often use yut to show spirit. For example, if an officer asks his troops if they are ready, they may all shout "Yut!" or "Yut yut!" in unison. Marines may also say "yut" to one another when joking around or roughhousing or to give a soldier praise for hard work.
Out of the service, Marines may issue yut to fellow Marines in speech or writing to signal previous service, pride, and fellowship with the Marine Corps as an organization.
Very occasionally, yut is heard as a dialect form of yes in New England, associated with Maine's ayuh.
PT PT every day, build your body the Marine Corps way. Yut.
@bordy, November, 2008
Yut is a military term. Marines say "Yut" when they're motivated, for a yes response and sometimes out of sarcasm.
@AnnBernard, August, 2008
It is clear that being the first of anything is incredibly important. The work ethic that is required to become a Marine Corps Infantry officer is extreme and admirable. Congrats to her. Yut Yut.
Chaps, Barstool Sports, September, 2017