over·​flow | \ ˌō-vər-ˈflō How to pronounce overflow (audio) \
overflowed; overflowing; overflows

Definition of overflow

 (Entry 1 of 2)

transitive verb

1 : to cover with or as if with water : inundate
2 : to flow over the brim of
3 : to cause to overflow

intransitive verb

1 : to flow over bounds
2 : to fill a space to capacity and spread beyond its limits the crowd overflowed into the street


over·​flow | \ ˈō-vər-ˌflō How to pronounce overflow (audio) \

Definition of overflow (Entry 2 of 2)

1 : a flowing over : inundation
2 : something that flows over : surplus
3 : an outlet or receptacle for surplus liquid

Keep scrolling for more

Synonyms & Antonyms for overflow

Synonyms: Verb


Synonyms: Noun

alluvion, bath, cataclysm, cataract, deluge, flood, flood tide, inundation, Niagara, spate, torrent

Antonyms: Noun

drought (also drouth)

Visit the Thesaurus for More 

Examples of overflow in a Sentence


The river overflowed its banks. The creek overflows every spring. The water in the tub overflowed. Books and papers overflowed his desk. The paragraph overflowed the page.


a great overflow of water from the heavy rains swept mud and silt down onto the highway an overflow of help actually made the job more complicated
See More

Recent Examples on the Web: Verb

The Harris County Flood Control District has plans for three maintenance projects in channels that typically overflow to reduce flooding in Kingwood this fall. Kaila Contreras, Houston Chronicle, "Harris County Flood Control plans $600,000 Kingwood maintenance projects," 6 Aug. 2019 In recent days, Puerto Ricans have used a variety of phrases to explain the effect the revelation of the crass messages has had on Puerto Ricans of all stripes: The last drop that overflowed the glass. Alejandra Rosa, New York Times, "‘The People Can’t Take It Anymore’: Puerto Rico Erupts in a Day of Protests," 22 July 2019 The venom that overflowed in the latter stages and after the final whistle in Portland's 2-1 win at CenturyLink Field Sunday night, for instance, is a product of all of that. Avi Creditor, SI.com, "The MLS XI, Week 20: Zlatan, Portland vs. Seattle and Games That Just Mean More," 22 July 2019 Mixing with the cigarette smoke was the smell of coffee that overflowed from its pot and burned on the plate by the hallway door. Ashley Strickland, CNN, "'We did the impossible': What it was like inside Apollo 11's Mission Control," 19 July 2019 Nearly every village Amstislavski visited had a dump overflowing with plastic. Devin Kelly, Anchorage Daily News, "Using fungi, UAA team develops biodegradable insulation for shipping Alaska seafood," 14 July 2019 Six garbage cans overflowing with plastic bags, loose pieces of clothing and paper waste line the McMicken curb like sentinels. Mark Curnutte, Cincinnati.com, "4 addresses in 4 months: This is what poverty looks like for this Cincinnati family," 10 July 2019 At least six roads in Tucson were closed because of flash flooding from washes that overflowed. Terry Tang, The Seattle Times, "Tropical Storm Rosa heads for Baja, US Southwest," 1 Oct. 2018 Needing to be at the restaurant so much of the time has cut into his home entertaining, although his kitchen resembles at outpost of a cookware store that overflows with Wüsthof knives and Calphalon pots and pans. Nancy Miller, The Courier-Journal, "Food at this Italian restaurant in Old Louisville isn't your nonna's," 5 June 2018

Recent Examples on the Web: Noun

View this post on Instagram Words truly can’t describe the overflow of love, tears and laughter that was shared on this beautiful, rainy day in Palm Springs. Katherine J. Igoe, Marie Claire, "Who Is Demi's Girlfriend Kristian Haggerty From 'Bachelor In Paradise'?," 19 July 2019 Heavy rain inundates the pipes, causing overflows of millions of gallons of stormwater laced with sewage. Scott Dance, baltimoresun.com, "Sampling initiative in Baltimore's Inner Harbor aims to answer the question, 'How's the water, hon?'," 25 June 2019 In April, the distillery failed to turn off a pump that was transferring wastewater, resulting in the overflow of a holding tank into a nearby tributary. Benjamin Tobin, The Courier-Journal, "It's been a year since Kentucky's huge bourbon barrel spill. What's changed?," 21 June 2019 That causes the runoff and sewage overflow that ultimately leads to potential contamination. Julian Gill, Houston Chronicle, "Ranked: The top 10 Texas beaches with contaminated, potentially unsafe water," 24 July 2019 Sources of pollution at beaches include urban runoff, sewage overflow and failing septic systems, and concentrated livestock manure, according to the report. Michelle Lou, CNN, "Beaches across America showed unsafe levels of pollution last year, a study finds," 23 July 2019 The primary sources of fecal contamination include urban runoff, sewage leaks and overflows and industrial-scale livestock operations. Leada Gore | Lgore@al.com, al.com, "List of ‘dirty’ beaches due to fecal bacteria includes 10 in Alabama, Florida," 23 July 2019 Often times, there might be a sewer overflow whenever there’s rain. Elise Takahama, The Seattle Times, "Several Seattle area beaches scheduled to reopen after Puget Sound sewage spill," 22 July 2019 The water flows up into the sink and into the overflow hole and back down to the trees. San Diego Union-Tribune, "La Mesa couple wins Otay Water District contest," 22 July 2019

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

See More

First Known Use of overflow


before the 12th century, in the meaning defined at transitive sense 1


1568, in the meaning defined at sense 1

Keep scrolling for more

Learn More about overflow

Statistics for overflow

Last Updated

10 Aug 2019

Look-up Popularity

Time Traveler for overflow

The first known use of overflow was before the 12th century

See more words from the same century

Keep scrolling for more

More Definitions for overflow



English Language Learners Definition of overflow

 (Entry 1 of 2)

: to flow over the edge or top of (something)
: to fill or cover (something) completely
: to be completely filled with something : to be so filled that there is not enough room for anything or anyone more



English Language Learners Definition of overflow (Entry 2 of 2)

: an act of flowing over the edge or top of something
: the amount of something that flows over the edge or top of something else
: the number of people or things that goes over a limit


over·​flow | \ ˌō-vər-ˈflō How to pronounce overflow (audio) \
overflowed; overflowing

Kids Definition of overflow

 (Entry 1 of 2)

1 : to flow over the top of The river overflowed its banks.
2 : to flow over bounds The creek overflows every spring.
3 : to fill or become filled beyond capacity The basket was overflowing with candy.
4 : to fill a space up and spread beyond its limits The crowd overflowed into the street.


over·​flow | \ ˈō-vər-ˌflō How to pronounce overflow (audio) \

Kids Definition of overflow (Entry 2 of 2)

1 : a flowing over Dams couldn't stop the overflow.
2 : something that flows over or fills a space and spreads beyond its limits Police tried to control the overflow of traffic.


over·​flow | \ ˈō-vər-ˌflō How to pronounce overflow (audio) \

Medical Definition of overflow

: an excessive flow or amount

Keep scrolling for more

More from Merriam-Webster on overflow

Rhyming Dictionary: Words that rhyme with overflow

Thesaurus: All synonyms and antonyms for overflow

Spanish Central: Translation of overflow

Nglish: Translation of overflow for Spanish Speakers

Britannica English: Translation of overflow for Arabic Speakers

Comments on overflow

What made you want to look up overflow? Please tell us where you read or heard it (including the quote, if possible).


a wrong name or inappropriate designation

Get Word of the Day daily email!

Test Your Vocabulary

Summer 2019 Words of the Day Quiz

  • a-bowl-of-peach-sorbet-with-cut-peaches-next-to-it
  • Which is a synonym of desideratum?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!


Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!