raft
A flat buoyant structure used as a boat or for floating on water. Common in outdoor and river contexts.
川でラフトに乗って下った。
We went down the river on a raft.
We all got on a raft and went down the river.
急流をラフトで下るツアーに参加した。
I joined a tour to go down the rapids by raft.
Borrowed from English 'raft'.