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 A decade of study there had identified a pattern of obscure illnesses affecting remote villagers who used bat guano as fertilizer and sometimes for medicine. Abrahm Lustgarten, ProPublica, "How Climate Change Is Contributing to Skyrocketing Rates of Infectious Disease," 7 May 2020 If the source of the virus is a wet market or natural exposure — say, a farmer going into a cave to collect guano to use as fertilizer — then the villains of the story are familiar and aligned the status quo. Jim Geraghty, National Review, "NPR’s Spotty Report on the Wuhan Labs," 27 Apr. 2020 Bat guano, or poop, is considered to be an excellent fertilizer, so it's mined from caves. Ashley Strickland, CNN, "Newly discovered bats are related to those associated with the pandemic," 22 Apr. 2020 Wildlife surveys conducted by EcoHealth Alliance in China and elsewhere in Asia show the highest prevalence of coronaviruses tend to be extruded by animals through feces, or guano in the case of bats. National Geographic, "New coronavirus can spread between humans—but it started in a wildlife market," 21 Jan. 2020 Investigators sifted through samples of bat saliva and excrement, known as guano, at locations in Myanmar where humans and bats cross paths. Zachary Halaschak, Washington Examiner, "Scientists discover six new coronaviruses in bats," 12 Apr. 2020 Researchers from Missouri and Virginia are studying what’s scientifically known as guano that was taken from Missouri caves, the St. Louis Post-Dispatch reported Monday. Washington Post, "‘Stinky’ bat guano could offer climate change insight," 11 Jan. 2020 For a half century in the late 19th and early 20th centuries, Redonda bustled with activity as the site of a mine that used a large pulley system to lower buckets of guano and phosphates—used as fertilizer—down to the shoreline below. National Geographic, "Ravenous wild goats ruled this island for over a century. Now, it's being reborn.," 2 Jan. 2020 The Cosmic Microwave Background was famously discovered by people working on a microwave receiver who couldn't get rid of an irritating source of noise—even after trying to clean out all the pigeon guano from the hardware. John Timmer, Ars Technica, "Bio-electronic device can produce electricity using nothing but humidity," 17 Feb. 2020

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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Time Traveler for guano

Time Traveler

The first known use of guano was in 1604

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Statistics for guano

Last Updated

22 May 2020

Cite this Entry

“Guano.” Dictionary, Merriam-Webster, Accessed 29 May. 2020.

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How to pronounce guano (audio)

English Language Learners Definition of guano

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

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Thesaurus: All synonyms and antonyms for guano

Rhyming Dictionary: Words that rhyme with guano

Spanish Central: Translation of guano Encyclopedia article about guano

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