dosatto
The dull, heavy sound of something bulky hitting the ground — a bag of rice dropping, a stack of books collapsing, or a person flopping down.
💡Dropping a heavy bag on the floor — 'The luggage landed dosatto on the floor.'
荷物をどさっと床に置いた。
I dropped the luggage dosatto on the floor.
He came home exhausted and ___ collapsed onto the sofa.
疲れて帰ってきてソファに○○と倒れ込んだ。