deep

1 of 3

adjective

1
: extending far from some surface or area: such as
a
: extending far downward
a deep well
a deep chasm
b(1)
: extending well inward from an outer surface
a deep gash
a deep-chested animal
(2)
: not located superficially within the body
deep pressure receptors in muscles
c
: extending well back from a surface accepted as front
a deep closet
d
: extending far laterally from the center
deep borders of lace
e
sports : occurring or located near the outer limits of the playing area
hit to deep right field
f
sports : thrown or hit for a considerable distance : thrown or hit deep (see deep entry 2 sense 3b)
a deep pass
a deep fly ball
2
: having a specified extension in an implied direction usually downward or backward
a shelf 20 inches deep
cars parked three-deep
3
a
: difficult to penetrate or comprehend : recondite
deep mathematical problems
deep discussions on the meaning of life
b
: mysterious, obscure
a deep dark secret
c
: grave or lamentable in nature or effect
in deepest disgrace
d
: of penetrating intellect : wise
a deep thinker
e
: intensely engrossed or immersed
She was deep in her book.
f
: characterized by profundity of feeling or quality
a deep sleep
also : deep-seated
deep religious beliefs
4
a
of color : high in saturation and low in lightness
a deep red
b
: having a low musical pitch (see pitch entry 4 sense 4b) or pitch range
a deep voice
5
a
: situated well within the boundaries
a house deep in the woods
b
: remote in time or space
found deep in rural England
c
: being below the level of consciousness
deep neuroses
d
: covered, enclosed, or filled to a specified degree
usually used in combination
ankle-deep in mud
6
: large
deep discounts
7
: having many good players
a deep bullpen
8
computing : having or using many repetitions of algorithmic processing
deep learning
deeply adverb
deepness noun

deep

2 of 3

adverb

1
: to a great depth : deeply
still waters run deep
tunneled deep into the earth
2
: far on : late
danced deep into the night
3
sports
a
: near the outer limits of the playing area
the shortstop was playing deep
b
: long sense 6
threw deep to the wide receiver
hit the ball deep to right field

deep

3 of 3

noun

1
a
: a vast or immeasurable extent : abyss
b(1)
: the extent of surrounding space or time
the azure deep
(2)
nautical : ocean
the briny deep
2
: any of the deep portions of a body of water
specifically : a generally long and narrow area in the ocean where the depth exceeds 3000 fathoms (5500 meters)
the Aldrich Deep in the south Pacific
3
: the middle or most intense part
in the deep of winter
4
nautical : any of the fathom points on a sounding line other than the marks (see mark entry 1 sense 2b)
Phrases
in deep water
: in difficulty or distress
Choose the Right Synonym for deep

broad, wide, deep mean having horizontal extent.

broad and wide apply to a surface measured or viewed from side to side.

a broad avenue

wide is more common when units of measurement are mentioned

rugs eight feet wide

or applied to unfilled space between limits.

a wide doorway

broad is preferred when full horizontal extent is considered.

broad shoulders

deep may indicate horizontal extent away from the observer or from a front or peripheral point.

a deep cupboard
deep woods

Examples of deep in a Sentence

Adjective We walked in the deep snow. a deep valley between the mountains The water is deepest in the middle of the lake. She's afraid of swimming in deep water. a plant with deep roots The house has lots of deep closets. She has a small but deep wound on her arm. This enormous canyon is over a mile deep. The shelves are 10 inches deep. He stepped into an ankle-deep puddle of mud. Adverb The ship now lies deep below the water's surface. Our feet sank deeper into the mud. The treasure was buried deep within the ground. Their secret offices were located deep underground. We walked deep into the forest. The soldiers are operating deep within enemy territory. I stood three feet deep in the water. He stepped ankle-deep into a puddle of mud. Noun the kind of cold weather that we usually have only in the deep of winter sailors exploring the farther reaches of the briny deep
Recent Examples on the Web
Adjective
Date of Brand Origin: 2015 Material: Polyamide, Polyester, and Cotton Colors Available: 1 Outdoor Research is one of those beloved companies that real outdoorsy types know and love because of its deep attention to detail and desire to create products that punch above their price points. William Goodman, Robb Report, 14 Mar. 2024 Bites can come anywhere, from under shallow docks to on the bottom in deep water. Joe Cermele, Field & Stream, 14 Mar. 2024 With its backroom graffiti, deep LP stock (there’s an original pressing of Big Star’s Radio City behind the counter!), stickers on every surface, and original promotional posters for the Eagles and the Grateful Dead, Karma Records has the feel of a museum, which Ector says is appropriate. Stephen Deusner, SPIN, 14 Mar. 2024 Editor Tip: The hybrid mattress has deep coils for support that are spread to increase ventilation, so heat doesn't get trapped inside. Sarah Madaus, Allure, 14 Mar. 2024 At the time, energy prices were in a deep slump because of Covid-19 lockdowns, prompting some speculation that oil demand had already peaked. Laura Hurst, Fortune Europe, 14 Mar. 2024 As well as targeting Russia’s deep oil reserves, Kyiv’s latest strikes may be partially intended to bring home to Russians the impact of the war just as the country prepares for a presidential election. Rob Picheta, CNN, 13 Mar. 2024 Earlier this week, the parents stepped out together on the Vanity Fair post-Oscars red carpet, the children’s book author looking stunning in a deep cobalt blue dress. Hannah Dailey, Billboard, 13 Mar. 2024 The agency expressed deep sadness over Friday’s death and said its thoughts were with the victim’s family. Joe Heim, Washington Post, 2 Mar. 2024
Adverb
That’s led many Democrats to search deep into the innards of polls in an often self-deluding search for error. David Lauter, Los Angeles Times, 15 Mar. 2024 The devices have two electrodes that target a pea-size structure deep inside the brain called the subthalamic nucleus. Brenda Goodman, CNN, 15 Mar. 2024 The site goes deep into Arizona’s backcountry, offering evidence of the daily life activities of the Apache community that originally inhabited the area and the decades of battles with the U.S. military forces. Laura Daniella Sepulveda, The Arizona Republic, 14 Mar. 2024 Best Pet Hair Remover: Uproot Cleaner Xtra This rake went deep into carpet pile to pull up fur that vacuums don’t always reach. Ella Field, Better Homes & Gardens, 13 Mar. 2024 Israel strikes targets in northern Lebanon; at least 2 dead A pair of Israeli airstrikes hit targets deep in northern Lebanon on Tuesday, killing at least two people and injuring at least 20 others, the Associated Press, citing a Lebanese security official. Christopher Cann, USA TODAY, 12 Mar. 2024 Come winter, the town's population balloons with skiers, snowboarders, and other snow-loving sports enthusiasts — perhaps even Olympic medalists deep in training. Anne Olivia Bauso, Travel + Leisure, 9 Mar. 2024 Ryan Raposo scored deep into first-half stoppage time to help the Vancouver Whitecaps salvage a 1-1 draw against visiting Charlotte FC on Saturday night. Observer Wire Reports, Charlotte Observer, 3 Mar. 2024 The kids crushed the slopes by day and the adults howled with laughter deep into the night. Ingrid Vasquez, Peoplemag, 1 Mar. 2024
Noun
Full-body deep fakes manipulate a person’s entire form, altering actions creating realistic videos. Richard Torrenzano, Fortune, 31 Jan. 2024 For now, President Joe Biden faces a couple of Democratic challengers, but is expected to secure his party's nomination, while former President Donald Trump and Florida Gov. Ron DeSantis have dominated the early Republican race in a field that is about a dozen deep. Democrat-Gazette Staff From Wire Reports, Arkansas Online, 31 Aug. 2023 Only the fifth task is what is ordinarily thought of as the primary one: to transport people into the dark, hostile deep. Ben Taub, The New Yorker, 1 July 2023 On third-and-4 from Pittsburgh’s 41, Williams appeared to have thrown an incomplete deep to Tre Walker, but Butler, the former Michigan State corner, was flagged for pass interference. Ryan Ford, Detroit Free Press, 25 June 2023 Aim for a pile that's 4' wide by 4' deep by 4' high. Arricca Elin Sansone, Country Living, 26 May 2023 Deep, deep in geologic time, some 600 million or 700 million years ago, the very first animals evolved on Earth. Viviane Callier, Scientific American, 17 May 2023 There are other plants in some of the locations; how close/deep/much to use in the root method without hurting other plants would be helpful to know. oregonlive, 26 Mar. 2023 Deep down, their actions may stem from deep insecurities, but their outward confidence often leads to them treating others badly without any consideration. Amy MacKelden, ELLE, 10 Mar. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'deep.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Adjective, Adverb, and Noun

Middle English dep, from Old English dēop; akin to Old High German tiof deep, Old English dyppan to dip — more at dip

First Known Use

Adjective

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

Adverb

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

Noun

before the 12th century, in the meaning defined at sense 1b(2)

Time Traveler
The first known use of deep was before the 12th century

Dictionary Entries Near deep

Cite this Entry

“Deep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deep. Accessed 19 Mar. 2024.

Kids Definition

deep

1 of 3 adjective
1
a
: extending far downward
a deep well
b
: having a great distance between the top and bottom surfaces : not shallow
deep water
c
: extending well inward from an outer or front surface
a deep gash
d
: extending far outward from a center
deep space
e
: occurring or located near the outer limits
deep right field
2
: having a specified extension downward or backward
a shelf 40 centimeters deep
3
a
: difficult to understand
a deep book
b
: mysterious, obscure
a deep dark secret
c
: profound sense 1
a deep thinker
d
: completely absorbed
deep in thought
e
: being to an extreme degree : heavy
deep sleep
4
a
: dark and rich in color
a deep red
b
: having a low musical pitch or range
a deep voice
5
a
: coming from or located well within
a deep sigh
a house deep in the forest
b
: covered, enclosed, or filled often to a specified degree
knee-deep in water
a road deep with snow
deeply adverb

deep

2 of 3 adverb
1
: to a great depth : deeply
2
: far on : late
read deep into the night
3
: near the outer limits
the shortstop was playing deep

deep

3 of 3 noun
1
a
: an extremely deep place or part (as of the ocean)
2
: the middle or most intense part
the deep of night

Medical Definition

deep

adjective
1
a
: extending well inward from an outer surface
a deep gash
b(1)
: not located superficially within the body or one of its parts
deep pressure receptors in muscles
(2)
: resulting from or involving stimulation of deep structures
deep pain
deep reflexes
2
: being below the level of the conscious
deep neuroses
deeply adverb

More from Merriam-Webster on deep

Last Updated: - Updated example sentences
Love words? Need even more definitions?

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