gua·​no | \ ˈgwä-(ˌ)nō How to pronounce guano (audio) \

Definition of guano

: a fertilizer containing the accumulated excrement of seabirds or bats broadly : excrement especially of seabirds or bats

Examples of guano in a Sentence

Recent Examples on the Web

Today, the Peruvian government carefully manages an annual guano harvest on certain coastal islands. Kiona N. Smith, Ars Technica, "New study takes a bird’s-eye view of the Nasca Lines," 20 June 2019 Their guano adds the nutrient nitrogen to the islands, leading to big changes in the ecosystem. Jason Daley, Smithsonian, "Coral Reefs Need Fewer Rats and More Bird Poo," 12 July 2018 The Incas used guano harvested from islands that dot Peru’s 1,500-mile coastline as fertilizer. Washington Post, "The unlikely treasure off Peru’s coast," 21 June 2018 The harvest target this year is about 20,000 tons of guano. Washington Post, "The unlikely treasure off Peru’s coast," 21 June 2018 New buds sprang eternal from the guano heap of Twitter, and thus continued the Outrage Circle of Life. New York Times, "News of an ‘Outrage’ Used to Mean Something Very, Very Different," 23 May 2018 Around the same time, Vogt was hired to study a baffling decline in seabird guano, then widely used as fertilizer., "Biographies highlight some key figures in environmentalism," 27 Apr. 2018 The crew's nightly flight in search of food, once an awe-inspiring festival of guano and flapping wings, was just a skeleton of its former self. Craig Hlavaty, Houston Chronicle, "Months after Harvey, see how the bat colony is faring at Waugh bridge," 17 Apr. 2018 Another perk: bat droppings, otherwise known as guano, act as a nutrient-dense fertilizer, making that garden of yours thrive like never before. Emily O'brien, Good Housekeeping, "5 Ways To Attract Bats To Your Yard," 20 Oct. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'guano.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of guano

1604, in the meaning defined above

History and Etymology for guano

Spanish, from Quechua wanu fertilizer, dung

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Statistics for guano

Last Updated

4 Jul 2019

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Time Traveler for guano

The first known use of guano was in 1604

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English Language Learners Definition of guano

: waste material from birds and bats that is used to help plants grow

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More from Merriam-Webster on guano

Rhyming Dictionary: Words that rhyme with guano

Spanish Central: Translation of guano Encyclopedia article about guano

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