Parents can learn about the terms and language they can expect to hear in children's films and TV shows in a new guide published by the British Board of Film Classification.
It comes as a survey carried out on behalf of the organisation showed that while most adults feel comfortable swearing or using strong language with friends, they do not in front of children, and do not want to hear more coarse or offensive words on screen.
The BBFC's guide covers the U, PG and 12A/12 categories, and classifies words including f*** as strong language, and c*** as very strong.
Acronyms that refer to expletives – such as WTF (What the f***) – are classified as if they are the words in full.
BBFC chief executive David Austin said: "Children are watching more content on multiple screens, and their parents want to protect them from strong and very strong language wherever they can and for as long as possible.
"Parents told us they are keen for media industries to share the responsibility – and that's where we come in.
"Very strong language retains an innate shock value, and for some remains the last taboo."
More from Ents & Arts
Harrison Ford tells young fan he is Indiana Jones's stunt double while on set in North Yorkshire
Ben Roberts: Actor who played Derek Conway in The Bill dies aged 70
COVID-19: Andrew Lloyd Webber says he will open theatres on 21 June – even if 'freedom day' is delayed
Noel Gallagher says Oasis break-up is the reason the band is now considered 'up there with the greats'
Dua Lipa revealed as most-played artist of 2020 after a bumper year of Brit and Grammy awards
Ellie Kemper: Actress apologises for attending 'racist, sexist, elitist' debutante ball as a teenager
In films categorised 12 or 12A there may be "moderate" bad language, the BBFC says on its website, and "strong language may be permitted, depending on the manner in which it is used, who is using the language, its frequency within the work as a whole and any special contextual justification".
PG films should have "mild bad language only", while U films can feature "infrequent use only of very mild bad language".
The BBFC's survey was commissioned to find out if parents would accept more frequent use of strong and very strong language in films watched by children and young teenagers.
Six in 10 respondents indicated that swearing is part of their daily life, with nearly a third (30%) saying they use strong language more than they did five years ago.
But six in 10 respondents also said that while they are comfortable using strong language with friends, they refrain from doing so if children can hear. Only one in five said they were comfortable swearing in front of children under 16 at home.
The research also suggested a generational divide when it comes to swearing, with nearly half (46%) of Generation Z respondents frequently using strong language daily, compared to only one in 10 (12%) of 55 to 64-year-olds and one in eight (12%) over-65s.
A quarter (25%) of 16 to 24-year-olds said they would never use strong language in public, compared to a majority of over-65s (75%), according to the results.
The research for the BBFC, carried out by Magenta, consisted of 76 participants who watched and reviewed films over 10 days, 17 online focus groups with a total of 66 participants, and an online survey of 1,000 adults aged 18 plus across the UK.