The Hollywood star was the Guest Announcer on the latest episode of the ITV family entertainment show and was tasked with guessing film titles acted out by families from their homes in game segment Saturday Night At The Movies.
Collette, 50, struggled to guess the title within the time limit as the Wilkinson family from Colchester attempted to act out the movie Dodgeball by wearing sweat bands and throwing red balls at one another.
She exclaimed: "Oh no I'm going to lose for them! S**t! Nobody help me."
— Saturday Night Takeaway (@itvtakeaway) March 18, 2023
As the audience gasped she then looked confused and asked: "What?!"
Hosts Ant McPartlin and Declan Donnelly told her, "You swore."
She then correctly guessed the film and the show quickly moved on to the next family.
The Australian actor - star of About A Boy, Muriel's Wedding, Little Miss Sunshine and The Sixth Sense - later said: "God, I wish my kids were here, they'd love this."
Collette has two sons 14-year-old daughter Sage Florence and 11-year-old Arlo Robert with her estranged husband Dave Galafassi. They announced they were divorcing amicably in December 2022.
After the commercial break hosts McPartlin and Donnelly apologised for the use of the swear word during the game saying, "Hope it didn't spoil it for you."
Going live to the home of another contestant they said: "Please don't swear. We've already had one tonight. We don't want another one."
The expletive was broadcast at around 7.20pm. The watershed for bad language is 9pm and broadcasters must pay fines to regulator Ofcom if swear words are aired before this time.
The first episode of the latest series of Saturday Night Takeaway was hit with complaints over a segment that saw a prank being played on a dad-to-be.
The prank saw the hosts secretly playing a long-running trick on a man named Liam in the months leading up to his son Finley's birth.
The joke, which the stars pulled off along with Liam's partner Amy, included scenes that showed the first time dad at a baby scan being fooled into thinking his baby was waving at him and dancing on screen.
However, while many viewers were tickled, Ofcom has now confirmed that 111 people complained about the episode.
And the broadcasting watchdog confirmed to Yahoo that the complaints related to the prank.
Watch: Ant and Dec prank Jeremy Clarkson on Saturday Night Takeaway