Referring to sweets as candy was one of the most commonly cited examples

"Trash" or "garbage" was the most commonly reported Americanism, cited by 44 per cent of respondents, followed closely by "candy" at about 40 per cent.

Other imported terms were less common: "Apartment" was heard by 14 per cent of teachers, "diaper" by nine per cent, and "movie theatre" by seven per cent.

Parental observations reinforce this trend, with many noting that Netflix and YouTube channels were major influences on their children's speech.

Stacie Swift, 39, from Cambridgeshire, is a mother of three and said she had noticed Americanisms "creeping into" her children's conversations.

"I've had to correct my children, who are ten and eight years old, as they slip into Americanisms," she said.

"They don't use them constantly, but every now and then they slip into conversation. It's usually because they have been watching American YouTube videos or cartoons."

Ana Louise Bonasera, a digital creator, said: "My child speaks with an American accent ... there was a new teaching assistant at school and they asked what part of America they were from!"

Karen Simpson, a former primary school teacher turned private tutor, said both of her children use Americanisms "all the time", with the words "candy" and "closet" regularly slipping into their speech.

Frank Young, who has a nine-year-old son, said: "The fragmentation of children's TV has a lot to answer for. Once children had RP accents on the BBC ... now young children are more likely to hear American accents and the words that go with it through streaming services well beyond the BBC.

"'Pavements' will become 'sidewalks' and 'taking out the rubbish' becomes 'taking out the garbage'. If that is all you hear, it is no wonder young children pick up Americanisms."

American influencers popular with teenagers include Jimmy Donaldson, better known as MrBeast, the YouTuber with 448 million subscribers; AMP, a collective creating challenges and gaming content; and Plaqueboymax, a YouTuber and record producer. The nursery YouTube channel CoComelon is popular among British children.

Linguists say that children's language is fluid and trends can be fleeting. Professor Lynne Murphy, who teaches British and American English at the University of Sussex, said that capturing accurate spoken data from young learners is challenging because by the time it is collected, children's speech has already evolved.

"We tend to rely on what's happening in adult language. That way, we can see what really became part of the language, and not just a fad," she said. "We adults don't talk like we did when we were four, or eight or 12, and neither will today's children."

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Murphy explained that children acquired vocabulary from a variety of sources, particularly online media, which allowed words from other countries to spread.

"The same is happening in the US, where British words can spread easily through popular media," she said.

"Just yesterday, an American contacted me to ask why everyone seems to be saying 'alongside' now. The answer was that it had recently transferred from Britain. But vocabulary is an additive thing -- having more of it allows us to do more with our language."

She explained that terms such as "movie" and "film" coexist. The same is true of "chips" and "fries" or "biscuits" and "cookies".

Evaluative words, such as "awesome" also tend to come and go, reflecting generational shifts in language rather than permanent change.

"What people tend to worry about is that the 'old' ways of saying things will be displaced. That sometimes happens, because the language is constantly being renewed. We don't talk like our parents or grandparents did, nor should we. At the same time, new words don't displace old words.

"English is a magpie language that loves adding vocabulary to communicate more precisely ... it has been a hybrid language since 1066. There's no reason for it to stop now."

Pepe Di'Iasio, general secretary of the Association of School and College Leaders, said: "Children absorb language readily, and as American culture is so prevalent, it is not surprising that Americanisms often crop up in classrooms and playgrounds.

"It is a common experience for teachers to hear words and phrases which derive not just from TV, films and other media but also from the conversations children have in their peer groups.

"Language is a voyage of discovery, constantly changing, shifting and transforming. It is part of the joy of teaching to see this happening around you."