Presenter Holly Willoughby appeared to swear live on This Morning during a cooking segment with chef Jamie Oliver.
The star, 38, was helping out by tossing veg in a frying pan as Jamie explained how to make a delicious festive vegetarian dish.
Jamie showed her how to properly toss the veg in the pan and when Holly had a go, she did it a bit too vigorously and some of the food spilled onto the hob.
She then appeared to say the 'S' word under her breath, but quickly realised what she had done and put a hand over her mouth.
Her co-host Phillip Schofield seemed to have heard it though, because he stood grinning at Holly and when she looked at him, he held a finger to his lips.
It was subtle but some viewers at home spotted it.
On Twitter, one said: "Holly thinking no one saw her swear #thismorning."
Don't worry, no-one noticed except me and Schofe.
Another wrote: "Oooohhhhhh you said a naughty word @hollywills #ThisMorning Don't worry, no-one noticed except me and @Schofe."
Someone else, sharing a clip of the moment, joked, "Naughty
@hollywills" with a string of laughing-crying emojis.
Elsewhere in the cooking segment, Holly narrowly escaped having her faced burnt off.
After she had a go at tossing the veg, Jamie took over and added a dash of brandy.
A column of red flames erupted from the pan and Holly, taken aback, screamed and leapt out of the way.
Jamie, clearly not phased by the sudden rush of heat, continued to work over the stove.
But Holly held a tea towel over her mouth in shock, and afterwards gasped: "Nearly took my head off! Oh my god, Jamie Oliver."
Phil teased her: "Great noise, I want that noise on my phone as a ringtone, whoop!"
Outside of This Morning, Holly and Phil have been filming for the new series of Dancing On Ice this week.Amid reports of a feud between the daytime TV favourites, the presenters joined the celeb line-up for the show's launch night on Monday (09.12.19).
And on Tuesday, they filmed scenes for the Dancing On Ice Christmas special.
Holly delighted her Instagram fans with a sweet clip from the special, in which she mimed All I Want For Christmas with Phil before throwing her arms around him and giving him a big hug.
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