Rachel Riley struggles to keep a straight face on 'Countdown' when she picks out letters that spell out "really weird" words.

Rachel Riley tries not to laugh at rude words on Countdown

Rachel Riley tries not to laugh at rude words on Countdown

The 37-year-old TV star has served as the letters and numbers assistant on the Channel 4 game show since taking over from series stalwart Carol Vorderman in 2008, but she has to try to avoid laughing when she puts potentially explicit words up on the board.

She told The Sun newspaper: "I get to chose what I put on the board on 'Countdown', the whole idea is to pull a straight face. There are some really weird stuff that comes out but that's the fun of it. Kids can watch but anyone with my kind of dirty sense of humour can watch."

During the letters round of the long-running game show - which sees contestants ask Rachel to select vowels and consonants at random so they can form the longest-possible word in 30 seconds - the presenter has been confronted with a string of potentially smutty words, including the likes of "bumh****", "perverts", "p***", "sugar t***" and "no panties."

The former 'Strictly Come Dancing' contestant is married to professional dancer Pasha Kovalev and has daughters Maven, three, and Noa, 16 months, with him.

Rachel went on to reveal that she accidentally taught her eldest some profanity.

She added: "I taught Maven some bad language during the football!"

Last year, Rachel's co-star Susie Dent - who has manned the show's Dictionary Corner for more than three decades - revealed the two of them often share bras and tights when they film the show.

She told Mail+: "For me, Rachel is also the very best of friends - strong, principled and utterly loyalty. I often think she and I are two sides of the same coin. She is always impeccably groomed while I frequently have dresses on inside out or back to front.

"She lends me bras, tights - anything, in fact, that I have characteristically left at home."