This tariff world you live in is a foreign concession. It's a foreign settlement in another country where foreigners get to make up all the rules, so they've gone and slapped tariffs on everything to annoy the country's native government.

租界 is most commonly used to refer to the foreign-controlled areas in China that had their own rules and law enforcement during the late 1800s and early 1900s. You'll mostly see it in historical contexts, but it's also sometimes used in fiction to describe foreign-controlled districts in imagined settings.

This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.