noun
rat guard
A physical barrier installed on pillars, ropes, pipes, etc. to prevent rats from climbing or passing. Often a metal or plastic disk or collar.
倉庫の柱にねずみ返しを取り付けた。
We installed rat guards on the warehouse pillars.
船の係留ロープにはねずみ返しが付いている
The ship's mooring ropes are fitted with rat guards.