Турецкое произношение säk aut
/ˈsak ˈout/ /ˈsæk ˈaʊt/
Этимология [ 'sak ] (noun.) before 12th century. Outgrowth of the earlier idiom, to hit the sack, with possible influences from other senses of to sack (tackle, pillage), and to sock (hit, slam), providing an implication that sleep has been thrust upon a person.