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Synonyms

shark

1 American  
[shahrk] / ʃɑrk /

noun

  1. any of a group of elongate elasmobranch, mostly marine fishes, certain species of which are large, voracious, and sometimes dangerous to humans.


idioms

  1. jump the shark, to begin a decline in quality, popularity, relevance, etc., after reaching a peak.

    Some TV shows have jumped the shark once a popular cast member left the show.

shark 2 American  
[shahrk] / ʃɑrk /

noun

  1. a person who preys greedily on others, as by cheating or usury.

  2. Informal. a person who has unusual ability in a particular field.


verb (used with object)

  1. Archaic. to obtain by trickery or fraud; steal.

verb (used without object)

  1. Archaic. to live by shifts and stratagems.

shark 1 British  
/ ʃɑːk /

noun

  1. a person who preys on or victimizes others, esp by swindling or extortion

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. archaic to obtain (something) by cheating or deception

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
shark 2 British  
/ ʃɑːk /

noun

  1. any of various usually ferocious selachian fishes, typically marine with a long body, two dorsal fins, rows of sharp teeth, and between five and seven gill slits on each side of the head

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • sharklike adjective

Etymology

Origin of shark1

First recorded in 1560–70; origin uncertain

Origin of shark2

1590–1600; < German dialect Schork, variant of Schurke rascal

Explanation

A shark is a large, carnivorous fish — although it's hard to calmly think, "That's just a large fish" when you run into a shark while you're swimming in the ocean. Almost all sharks live in the ocean, and while most of them are predators, the very largest sharks feed on plankton and tiny things like fish eggs. There are over four hundred species of shark, but only four have ever harmed humans; nevertheless, people have been afraid of these large, powerful animals for a long time. This dislike gave rise to the informal meaning of shark, "a person who swindles or preys on others."

Keep Reading on Vocabulary.com

Vocabulary lists containing shark

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

He made the shark cage himself and tried to use correct brands where possible.

From BBC • Apr. 4, 2026

“These companies, they’re like a shark, they have to keep moving,” said Christopher Whalen of the credit-markets research and advisory firm Whalen Global Advisors.

From The Wall Street Journal • Apr. 2, 2026

An 8-foot great white shark was spotted circling a surfer in Newport Beach on Thursday afternoon, triggering an immediate shutdown of the nearby shoreline, authorities said.

From Los Angeles Times • Mar. 26, 2026

The young shark measured about 210 cm in length and weighed roughly 80-90 kg.

From Science Daily • Mar. 11, 2026

Listening to Chicken talk about sharks made Cat think about a specific shark.

From "Caterpillar Summer" by Gillian McDunn