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adjective \ˈdēp\

Simple Definition of deep

  • : having a large distance to the bottom from the surface or highest point

  • : going far inward from the outside or the front edge of something

  • : located far inside something

Full Definition of deep

  1. 1 :  extending far from some surface or area: as a :  extending far downward <a deep well> 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 :  occurring or located near the outer limits of the playing area <hit to deep right field> f :  thrown deep <a deep pass>

  2. 2 :  having a specified extension in an implied direction usually downward or backward <a shelf 20 inches deep> <cars parked three-deep>

  3. 3 a :  difficult to penetrate or comprehend :  recondite <deep mathematical problems> b :  mysterious, obscure <a deep dark secret> c :  grave 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. 4 a of color :  high in saturation and low in lightness b :  having a low musical pitch or pitch range <a deep voice>

  5. 5 a :  situated well within the boundaries <a house deep in the woods> b :  remote in time or space 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. 6 :  large <deep discounts>

  7. 7 :  having many good players <a deep bull pen>

deep·ly adverb
deep·ness noun
in deep water
  1. :  in difficulty or distress

Examples of deep

  1. We walked in the deep snow.

  2. a deep valley between the mountains

  3. The water is deepest in the middle of the lake.

  4. She's afraid of swimming in deep water.

  5. a plant with deep roots

  6. The house has lots of deep closets.

  7. She has a small but deep wound on her arm.

  8. This enormous canyon is over a mile deep.

  9. The shelves are 10 inches deep.

  10. He stepped into an ankle-deep puddle of mud.

Origin of deep

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: before 12th century

Synonym Discussion of 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>.




Simple Definition of deep

  • : far into or below the surface of something

  • : far into or inside something

  • : at a specified measurement downward, inward, or backward

Full Definition of deep

  1. 1 :  to a great depth :  deeply <still waters run deep>

  2. 2 :  far on :  late <danced deep into the night>

  3. 3 a :  near the outer limits of the playing area <the shortstop was playing deep> b :  long 6

Examples of deep

  1. The ship now lies deep below the water's surface.

  2. Our feet sank deeper into the mud.

  3. The treasure was buried deep within the ground.

  4. Their secret offices were located deep underground.

  5. We walked deep into the forest.

  6. The soldiers are operating deep within enemy territory.

  7. I stood three feet deep in the water.

  8. He stepped ankle-deep into a puddle of mud.

Before 12th Century

First Known Use of deep

before 12th century




Definition of deep

  1. 1 a :  a vast or immeasurable extent :  abyss b (1) :  the extent of surrounding space or time (2) :  ocean

  2. 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)

  3. 3 :  the middle or most intense part <the deep of winter>

  4. 4 :  any of the fathom points on a sounding line other than the marks

Examples of deep

  1. <the kind of cold weather that we usually have only in the deep of winter>

  2. <sailors exploring the farther reaches of the briny deep>

Before 12th Century

First Known Use of deep

before 12th century

Medical Dictionary


adjective \ˈdēp\

Medical Definition of deep

  1. 1a:  extending well inward from an outer surface <a deep gash>b:  not located superficially within the body or one of its parts <deep pressure receptors in muscles>:  resulting from or involving stimulation of deep structures <deep pain> <deep reflexes>

  2. 2:  being below the level of the conscious <deep neuroses>

  3. deep·ly adverb

Seen and Heard

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February 14, 2016

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