Jennifer Aniston and Lisa Kudrow starred in Jimmy Kimmel's swearing game "Celebrity Curse Off" last night, and it was hilarious.

The former Friends co-stars participated in the contest to see who has the foulest mouth on late night show Jimmy Kimmel Live, uttering as many curse words as they could muster. And we were delighted to see they are both pretty impressive when it came to inventive curses! 

"Here at the show we’re known for bleeping and blurring things unnecessarily - but for once, the bleeping is necessary. If you are faint of heart cover your ears because it's time once again for America's most foul-mouthed competition," said Kimmel as he called up Aniston, 45, and Kudrow, 51.

The rules of the quick fire-style competition are that each star is given five seconds to come up with a curse and each word can only be used once.

The pair brought back memories of when they worked together on Friends from 1994 to 2004. When Kudrow uttered, "f***ing s***" Aniston laughed, "You used to say all the time".

The pair continued to giggle at words such as "a**wipe", "malaka," which Aniston says is a Greek swear term and Kudrow's attempt to swear in French. 

The actresses follow in the footsteps of Julia Roberts and Sally Fields who were the first stars to participate in Kimmel's expletive tournament. 

Find out who won in the swearing games between Jennifer Aniston and Lisa Kudrow in the video below.