Enid Blyton, pictured here in 1949 sitting in her garden in Beaconsfield, Buckinghamshire, wrote 21 Famous Five books between 1942 and 1963. (George Konig/Getty Images)

The British publisher of Enid Blyton's Famous Five children's book series says it's updating some of the phrases and words used in the bestselling series.

Hodder Children's Books has announced it's giving the first 10 books from Blyton's classic series a makeover after research showed children weren't enjoying the series as much due to the outdated language.

The Famous Five books — chronicling the adventures of siblings Julian, Dick and Anne with their cousin Georgina (George) and her dog Timmy — were first published between 1942 and 1963.

"There's no change to the plot whatsoever," Anne McNeil, publishing director of Hodder Children's Books, told the Guardian newspaper.

"Children who read [the Famous Five books] need to be able to easily understand the characterizations and easily to get into the plots. If the text is revised [they're] more likely to be able to engage with them."

Some of the revisions include:

• Housemistress to teacher.
• School tunic to uniform.
• Mother and father to mum and dad.
• Dirty tinker to traveller.
• Awful swotter to bookworm.

McNeil points out her company will continue to publish the old versions but plans to roll out the modern versions over the next seven months, starting in August.

The emphasis will be on making the language "timeless" rather than using any modern slang.

Tony Summerfield, who heads the Enid Blyton Society in the U.K., is not so enamored with the changes.

"I am in approval of changing language which has perhaps become offensive or has different meanings, or any racist references," he told the Guardian.

"Why does Blyton have to be so heavily altered when other authors from the same era aren't changed at all?"

McNeil acknowledges some of Blyton's fans won't like the revisions but points out the author herself, who died in 1968, was an advocate of children's literacy and would especially want children to be able to relate to her characters.

There are 21 Famous Five books in all and McNeil says, depending on the popularity of the updated versions, Hodder may continue revising the rest of the books. More than two million of the books are sold around the world every year.

A 2008 British survey named Blyton the "the U.K.'s most cherished and best-loved" author, followed by Roald Dahl and J.K. Rowling.