A few weeks back, primary school teacher Margherita Aurora, in the small town of Copparo in central Italy, was intrigued when one of her students, Matteo, used an unfamiliar word in a written assignment.
Matteo described a flower as "petaloso" ("full of petals"). The word doesn't officially exist in the Italian dictionary, but grammatically it makes sense as a combination of "petalo" ("petal") and the suffix "-oso" ("full of").
The assignment got Aurora thinking - could the eight-year-old Matteo have invented a new word? With his teacher's help, the student wrote to the Accademia della Crusca - the institution that oversees the use of the Italian language - to ask for their opinion.
To their surprise, the pair got an encouraging reply.
"The word you invented is well formed and could be used in the Italian language," one of the Crusca's top linguistic experts wrote. "It is beautiful and clear."
But, the linguist added, for a word to officially be part of the Italian language, a large number of people need to use it and understand its meaning. "If you manage to spread your word among many people who start saying 'What a petaloso flower this is!', then petaloso will have become a word in Italian."
Matteo's teacher was touched by the reply - "this is worth more than a thousand Italian lessons" she wrote on her Facebook account on Monday - and shared pictures of the letter.
Inadvertently, she triggered a movement to do exactly what the Crusca had asked: make "petaloso" a widely known and used word.
Her original Facebook post has been shared more than 80,000 times. On Twitter #petaloso was used almost 40,000 times. The word quickly became the top trending topic in Italy and briefly hit the list of top worldwide trends on Wednesday. Many tweeters used the word in context - demonstrating its wide use and commonly understood meaning.
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The Crusca itself - an institution created in 1583 - joined in the online effort and retweeted messages using the word. The Zanichelli publishing house - which publishes one of most widely referenced Italian dictionaries - hinted that it would include the word in its next edition. Italian Prime Minister Matteo Renzi even chipped in to congratulate the young student.
"Petaloso" is now well on its way to becoming an official Italian word thanks to an eight-year-old's imagination - and the power of social media.
There is, by the way, a direct equivalent in English: "petalous" has been a word since at least the early 18th century.
Blog by Julian Miglierini, BBC Rome
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