half-hitch; half knot; slipknot
A simple knot often used as a temporary or preliminary knot; can refer to a half-hitch or a slipknot depending on context.
I temporarily secured the rope to the post with a half-hitch.
片 (kata, 'one side') + 結び (musubi, 'knot'), referring to a knot that is tied only on one side or is incomplete compared to a full knot.