Currency
noun, の adjective
The thing that will pass through freight is currency. Why? Because when you want freight to be your own, you have to put money through it and to the person who owns it. When you do that, it becomes yours. Use that currency!
つうか
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
私はこの通貨をよく知っています。
I am quite familiar with this currency.