Definition

1. Adjective:

   • Extending far down from the top or surface: Having a great distance from the top or surface to the bottom.
   • Extending far back from the front or from an outer surface: Having a great distance inward.
   • Of a low sound or musical pitch: Low in tone or frequency.
   • Of a color: Strong and dark; not pale.
   • Very intense or extreme: To a great degree; profound.
   • Difficult to understand: Involving great complexity or obscurity; abstruse.
   • Involved to a great extent: Fully absorbed or engrossed in something.
   • Coming from or involving one's innermost feelings: Sincere and profound.

2. Adverb:

   • Far down or in: To a great depth or distance inward.
   • Far on in time: To a late point in time.
   • To a great extent: Profoundly or intensely.

3. Noun (literary):

   • The sea or ocean: The vast body of salt water.
   • A deep part of something: The most profound or central part, especially of a period of time.

Usage and Examples

• Adjective:

  • The lake is very deep here. (Describing physical depth)
  • She has a deep voice. (Describing a low vocal pitch)
  • They were in deep trouble. (Describing a severe situation)
  • He is a deep thinker. (Describing profound thought)
  • The book is too deep for me. (Describing something difficult to understand)
  • She is deep in thought. (Describing being fully absorbed)

• Adverb:

  • He buried the treasure deep underground. (Describing distance down)
  • We talked deep into the night. (Describing a late time)
  • I am deeply grateful for your help. (Note: The adverbial form is often "deeply" for figurative meanings like emotion.)

• Noun:

  • Strange creatures live in the deep. (Referring to the ocean)
  • In the deep of winter, the nights are long. (Referring to the most intense part of a period)

Advanced Usage and Nuances

• "Go deep": To become fully involved in or committed to something.
  • The investigation will go deep into the organization's finances.
• "In deep water": In a difficult or troublesome situation.
  • He's in deep water after missing the deadline.
• "Deep down": In one's true, often hidden, feelings or nature.
  • Deep down, she knew the truth.

Variants and Related Words

• Deeply (adverb): To a profound or intense degree. Used more commonly than "deep" as an adverb for figurative meanings (e.g., , ).
• Deepen (verb): To make or become deeper.
  • The crack deepened over time.
• Depth (noun): The distance from the top or surface to the bottom of something; intellectual complexity or intensity.
  • We measured the depth of the pool.

Synonyms

• Adjective (physical): Bottomless, cavernous, yawning.
• Adjective (profound): Intense, profound, heartfelt, abstruse, recondite.
• Adjective (low sound): Low-pitched, bass, sonorous.
• Adjective (dark color): Dark, rich, intense.
• Noun (sea): Ocean, main, brine (poetic).

Antonyms

• Adjective (physical): Shallow, superficial.
• Adjective (profound): Superficial, trivial, simple.
• Adjective (sound): High-pitched, shrill.
• Adjective (color): Light, pale, pastel.

Idioms and Phrases

• Still waters run deep: A quiet or placid person often has a profound or complex character.
• Throw someone in at the deep end: To force someone to start a new and difficult job or activity without help or preparation.
• Between the devil and the deep blue sea: Faced with two equally undesirable alternatives.
• Knee-deep in something: Very involved in something, especially something problematic or time-consuming.
  • He's knee-deep in paperwork.

Noun

1. literary term for an ocean
   • denizens of the deep
2. a long steep-sided depression in the ocean floor
3. the central and most intense or profound part
   • in the deep of night
   • in the deep of winter

Adjective

1. exhibiting great cunning usually with secrecy
   • deep political machinations
   • a deep plot
2. difficult to penetrate; incomprehensible to one of ordinary understanding or knowledge
   • the professor's lectures were so abstruse that students tended to avoid them
   • a deep metaphysical theory
   • some recondite problem in historiography
3. of an obscure nature
   • the new insurance policy is written without cryptic or mysterious terms
   • a deep dark secret
   • the inscrutable workings of Providence
   • in its mysterious past it encompasses all the dim origins of life- Rachel Carson
   • rituals totally mystifying to visitors from other lands
4. with head or back bent low
   • a deep bow
5. large in quantity or size
   • deep cuts in the budget
6. (of darkness) very intense
   • thick night
   • thick darkness
   • a face in deep shadow
   • deep night
7. extending relatively far inward
   • a deep border
8. relatively thick from top to bottom
   • deep carpets
   • deep snow
9. strong; intense
   • deep purple
   • a rich red
10. having or denoting a low vocal or instrumental range
    • a deep voice
    • a bass voice is lower than a baritone voice
    • a bass clarinet
11. extreme
    • in deep trouble
    • deep happiness
12. very distant in time or space
    • deep in the past
    • deep in enemy territory
    • deep in the woods
    • a deep space probe
13. having great spatial extension or penetration downward or inward from an outer surface or backward or laterally or outward from a center; sometimes used in combination
    • a deep well
    • a deep dive
    • deep water
    • a deep casserole
    • a deep gash
    • deep massage
    • deep pressure receptors in muscles
    • deep shelves
    • a deep closet
    • surrounded by a deep yard
    • hit the ball to deep center field
    • in deep space
    • waist-deep
14. marked by depth of thinking
    • deep thoughts
    • a deep allegory
15. relatively deep or strong; affecting one deeply
    • a deep breath
    • a deep sigh
    • deep concentration
    • deep emotion
    • a deep trance
    • in a deep sleep

Adverb

1. to a great distance
   • penetrated deep into enemy territory
   • went deep into the woods
2. to an advanced time
   • deep into the night
   • talked late into the evening
3. to a great depth; far down
   • dived deeply
   • dug deep