In Toontown Rewritten, a Unite phrase is obtained through defeating the cashbot Cheif Financial Officer. You will get one phrase per battle, which will always be randomized. You can get either a Jellybean Phrase, a Toonup Phrase, or a Gag Restock Phrase.
Jellybean and Toonup phrases will give a set amount of jellybeans/laff points to toons in a small area, and can be activated by saying them in chat.
A gag restock phrase restocks a specific kind of gag for all toons in a small area, and can be activated by saying them in chat.