勒 (lēi): สายรัดแน่น

Before hiking, he carefully tightened the backpack's shoulder straps so they wouldn't shift on the way.

Mom tied the zongzi tightly with a red string, saying that way they wouldn't fall apart when boiled.

He thought the seatbelt was strapped too tight, so he secretly loosened it a bit, but his dad saw him in the rearview mirror.