Microsoft will release an online version of its Encarta World English Dictionary free of charge this spring.
The dictionary, which is due to go live on 17 April, will offer easy-to-understand definitions with audio pronunciations.
The move follows rival Encyclopedia Britannica, which is offering its entire range of reference books online for no charge. But unlike Microsoft, Encyclopedia Britannica has opted for an advertising revenue generating model.
Microsoft's online dictionary includes definitions, word origins and essays from the CD-Rom version of Encarta World English Dictionary released in August 1999.
"Encarta World English Dictionary is one of the first dictionaries created with the help of the internet, making it a natural fit to be offered online," said Craig Bartholomew, general manager of Microsoft's learning business unit. "We have thousands of audio pronunciations in the dictionary and it's thoroughly up to date on the use of English around the world."
Cotton seedling freezes to death as Chang'e-4 shuts down for the Moon's 14-day lunar night
Fortnite easily out-earns PUBG, Assassin's Creed Odyssey and Red Dead Redemption 2 in 2018
Meteor showers as a service will be visible for about 100 kilometres in all directions
Saturn's rings only formed in the past 100 million years, suggests analysis of Cassini space probe data
New findings contradict conventional belief that Saturn's rings were formed along with the planet about 4.5 billion years ago