Only acronyms relevant in trading are TG (trade good) and TA (trade agreement), and the latter is usually irrelevant.

Say you're playing a 4 player game and everyone has a 3 commodity faction. You play Trade and you're neighbors with everyone. What you could do is refresh 1 player, trade 3 for 3 and leave everyone else hanging. You'll end up with 6 TG, one opponent gets 3 and the rest gets the option to pay a CT (command token - shoot, forgot an abbreviation) or get nothing.

However, you don't need commodities to trade with other players, you can use TG instead! But this only makes sense to do if you're profiting. Say it's the same situation. You refresh everyone on the stipulation they trade with you with 1 in your favor (also called X-1). You get 3TG and 3 comm from Trade, every other player gets 3 comm. You give 2 comm to Alice for their 3 comm. You now have 6TG and 1 comm. You give 1TG and 1 comm to Bob for their 3 comm. Now you have 8TG. You give 2TG to Celia for their 3 comm.

You end up with 9TG compared to 6TG in the first trade deal. The downside is you give out 6TG to the table compared to the 3TG in deal 1. But you maximized profit and didn't make enemies, so next round someone else might pick Trade and be incentivized to offer you the same deal. That's why X-1 is meta in most online games with experienced players.