noun
trading business; trade industry
Refers to the business sector or industry involved in international or domestic trade.
彼は貿易業に携わっている。
He is engaged in the trading business.
貿易業は国際情勢の影響を受けやすい。
The trade industry is easily affected by international situations.
商社 is a trading company, whereas 貿易業 is the broader industry or business category.
Compound of 貿易 (trade) and 業 (business/industry).