Good Morning Britain host Lorraine Kelly warned Andi Peters to stop saying a word which had an extremely vulgar meaning on Urban Dictionary.
Andi has been announcing the show's competitions and how to enter, live from his shed at home.
He used the word "gongoozler", which officially means "a person who enjoys watching activity on the canals of the United Kingdom".
The word was introduced on the show by guest Gyles Brandreth, who was likely unaware of its alternative meaning.
But some baffled viewers looked up the definition of the word and were met with the rather graphic sex act on Urban Dictionary.
They then got in touch with the show to complain, so Lorraine scolded Andi and warned him it was a "naughty word".
Lorraine said: "Gyles Brandreth gave us a word earlier on, Andi I don't ever want you to use that, we've had a few tweets and apparently the word is very naughty. So don't use it ok?"
"Yes, zipped up," replied Andi.
One viewer tweeted: " @andipeters well I so wish my curiosity hadn’t got the better of me from looking up gongoozle on the internet #lorraine @GMB ".
Another joked: " @ITVGMBritain @gylesbrandreth I too like @fansoflorraine thought gongoozle was a fab word until I looked up it's true meaning....and it's nothing to do with gazing at water.
"Did #susiedent really introduce you to that word? :-o".
Another warned Lorraine: " @reallorraine don’t use that word gongoozle! Look it up in the urban dictionary!".
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* Good Morning Britain airs on weekdays on ITV at 6am
