noun
protective tariff
A tariff rate set to protect domestic industries from foreign competition.
政府は国内産業を守るために保護関税率を引き上げた。
The government raised protective tariffs to safeguard domestic industries.
関税 is a general term for customs duties or tariffs, while 保護関税率 specifically refers to the rate of a protective tariff.
Compound of 保護 (protection) + 関税 (tariff) + 率 (rate).