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Synonyms

deep

American  
[deep] / dip /

adjective

deeper, deepest
  1. extending far down from the top or surface.

    a deep well;

    a deep valley.

    Antonyms:
    shallow
  2. extending far in or back from the front or from an edge, surface, opening, etc., considered as the front.

    a deep shelf.

  3. extending far in width; broad.

    deep lace;

    a deep border.

  4. ranging far from the earth and sun.

    a deep space probe.

  5. having a specified dimension in depth.

    a tank 8 feet deep.

  6. covered or immersed to a specified depth (often used in combination).

    standing knee-deep in water.

  7. having a specified width or number of items from front to back (often used in combination).

    shelves that are 10 inches deep;

    cars lined up at the entrance gates three-deep.

  8. extending or cutting far down relative to the surface of a given object.

    The knife made a deep scar in the table.

  9. situated far down, in, or back.

    deep below the surface;

    deep in the woods.

  10. reaching or advancing far down.

    a deep dive.

    Antonyms:
    shallow
  11. coming from far down.

    a deep breath.

  12. made with the body bent or lowered to a considerable degree.

    a deep bow.

  13. immersed or submerged in or heavily covered with (followed byin ).

    a road deep in mud.

  14. difficult to penetrate or understand; abstruse.

    a deep allegory.

    Synonyms:
    obscure, mysterious, recondite
  15. not superficial; profound.

    deep thoughts.

  16. grave or serious.

    deep disgrace.

  17. heartfelt; sincere.

    deep affections.

  18. absorbing; engrossing.

    deep study.

  19. great in measure; intense; extreme.

    deep sorrow.

  20. sound and heavy.

    deep sleep.

  21. (of colors) dark and vivid.

    a deep red.

  22. low in pitch, as sound, a voice, or the like.

    deep, sonorous tones.

  23. having penetrating intellectual powers.

    a deep scholar.

    Synonyms:
    sagacious, shrewd, intelligent, wise
  24. profoundly cunning or artful.

    a deep and crafty scheme.

  25. mysterious; obscure.

    deep, dark secrets.

  26. immersed or involved; enveloped.

    a man deep in debt.

  27. absorbed; engrossed.

    deep in thought.

  28. Baseball. relatively far from home plate.

    He hit the ball into deep center field.

  29. Linguistics. belonging to an early stage in the transformational derivation of a sentence; belonging to the deep structure.


noun

  1. the deep part of a body of water, especially an area of the ocean floor having a depth greater than 18,000 feet (5,400 meters).

  2. a vast extent, as of space or time.

  3. the part of greatest intensity, as of winter.

  4. Nautical. any of the unmarked levels, one fathom apart, on a deep-sea lead line.

  5. Chiefly Literary. the deep, the sea or ocean.

    He was laid to rest in the deep.

adverb

deeper, deepest
  1. to or at a considerable or specified depth.

    The boat rode deep in the water.

  2. far on in time.

    He claimed he could see deep into the future.

  3. profoundly; intensely.

  4. Baseball. at or to a deep place or position.

    The outfielders played deep, knowing the batter's reputation as a slugger.

idioms

  1. in deep,

    1. inextricably involved.

    2. having made or committed oneself to make a large financial investment.

  2. go off the deep end,

    1. to enter upon a course of action with heedless or irresponsible indifference to consequences.

    2. to become emotionally overwrought.

  3. in deep water,

    1. in difficult or serious circumstances; in trouble.

    2. in a situation beyond the range of one's capability or skill.

      You're a good student, but you'll be in deep water in medical school.

deep British  
/ diːp /

adjective

  1. extending or situated relatively far down from a surface

    a deep pool

  2. extending or situated relatively far inwards, backwards, or sideways

    a deep border of trees

  3. cricket relatively far from the pitch

    the deep field

    deep third man

    1. (postpositive) of a specified dimension downwards, inwards, or backwards

      six feet deep

    2. ( in combination )

      a six-foot-deep trench

  4. coming from or penetrating to a great depth

    a deep breath

  5. difficult to understand or penetrate; abstruse

  6. learned or intellectually demanding

    a deep discussion

  7. of great intensity; extreme

    deep happiness

    deep trouble

  8. absorbed or enveloped (by); engrossed or immersed (in)

    deep in study

    deep in debt

  9. very cunning or crafty; devious

    a deep plot

  10. mysterious or obscure

    a deep secret

  11. (of a colour) having an intense or dark hue

  12. low in pitch or tone

    a deep voice

  13. informal

    1. to lose one's temper; react angrily

    2. to act rashly

  14. in a tricky position or in trouble

  15. See end 1

"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

noun

  1. any deep place on land or under water, esp below 6000 metres (3000 fathoms)

    1. a poetic term for the ocean

    2. cricket the area of the field relatively far from the pitch

  2. the most profound, intense, or central part

    the deep of winter

  3. a vast extent, as of space or time

  4. nautical one of the intervals on a sounding lead, one fathom apart

"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

adverb

  1. far on in time; late

    they worked deep into the night

  2. profoundly or intensely

  3. informal in reality, esp as opposed to appearance

    she is a very kind person deep down

  4. long ago

"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
deep More Idioms  

    More idioms and phrases containing deep


Other Word Forms

  • deeply adverb
  • deepness noun
  • nondeep adjective
  • overdeep adjective
  • undeep adjective
  • undeeply adverb

Etymology

Origin of deep

First recorded before 900; Middle English dep, Old English dēop; akin to Gothic diups, Old Norse djupr, Dutch diep, Old High German tiof; akin to dip 1 ( def. ), dive ( def. )

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.

More than two decades ago, Dudley proposed that humans' interest in alcohol has deep roots in primate evolution and stems from ancient foraging habits.

From Science Daily

Looking ahead, Watanabe hopes to apply the zap-and-freeze method to brain tissue collected, with permission, from individuals with Parkinson's disease who are undergoing deep brain stimulation procedures.

From Science Daily

At the time, Mr Hughes said he was "personally mortified" by the mistake and acknowledged the "deep disruption" it caused.

From BBC

"Fast flowing or deep floodwater is possible, causing a danger to life, " it added.

From BBC

Quarterback Michael Gonzalez said there was only one play to call — the “everybody go deep play.”

From Los Angeles Times