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¹deep

adjective \ˈdēp\

: 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

: 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>

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

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>

a of color : high in saturation and low in lightness

b : having a low musical pitch or pitch range <a deep voice>

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>

: large <deep discounts>

: having many good players <a deep bull pen>

— deep·ly adverb

— deep·ness noun

— in deep water

: in difficulty or distress

See deep defined for English-language learners

See deep defined for kids

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

Related to DEEP

Synonyms: abysmal, bottomless, profound

Antonyms: shallow, shoal, skin-deep, superficial, surface

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>.

Other Anatomy Terms

bilateral symmetry, carotid, cartilage, dorsal, entrails, prehensile, renal, solar plexus, supine, thoracic, ventral

²deep

adverb

: 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

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

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

a : near the outer limits of the playing area <the shortstop was playing deep>

b : long 6

See deep defined for English-language learners

First Known Use of DEEP

before 12th century

³deep

noun

Definition of DEEP

a : a vast or immeasurable extent : abyss

b (1) : the extent of surrounding space or time (2) : ocean

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

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

See deep defined for English-language learners

First Known Use of DEEP

before 12th century

Related to DEEP

Synonyms: thick, depth, height, middle, midst

IN DEEP WATER Defined for Kids

¹deep

adjective \ˈdēp\

deep·erdeep·est

Definition of DEEP for Kids

: reaching far down below the surface

: reaching far inward or back from the front or outer part <a deep cut> <a deep closet>

: located well below the surface or well within the boundaries of <deep in the ground>

: coming from well within <a deep sigh>

: completely absorbed <deep in thought>

: hard to understand <This story is too deep for me.>

: mysterious <a deep, dark secret>

: extreme in degree : heavy <a deep sleep>

: dark and rich in color <a deep red>

: low in tone <a deep voice>

— deep·ly adverb

²deep

adverb

deep·erdeep·est

Definition of DEEP for Kids

: to a great depth : deeply

: ²late 1 <She read deep into the night.>

³deep

noun

Definition of DEEP for Kids

: a very deep place or part <the ocean deeps>

: ocean 1 <Pirates sailed the briny deep.>

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

Medical Dictionary

deep

adjective \ˈdēp\

Medical Definition of DEEP

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>

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

—deep·ly adverb