Bosses at TV's Countdown had to axe a round after a contestant offered up an expletive during filming of an edition, Channel 4 has said.
Competitors on the long-running Channel 4 show, in which people make the longest word from a selection of letters, were given DTCEIASHF.
But they were given a new set of letters and asked to try again when Cambridge University student Jack Hurst produced the word "s**tface".
Dictionary corner expert Susie Dent told presenter Jeff Stelling the term for a "rude or obnoxious person" would have been acceptable.
However the station decided it was not suitable and a fresh selection of letters was used.
Channel 4 said: "Countdown is a daytime programme and this particular word was not deemed appropriate for a daytime audience so not included in the show."
Maths student Hurst, 18, won eight shows during his stint on the programme last month, achieving the highest ever total for an "octochamp".
Countdown was the first show broadcast on Channel 4 when it launched in November 1982, and has since become a national institution.