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deep

adj. · adv. · n. · v.
US //ˈdip// UK //dˈiːp// deep
  1. 1 far down or in (adj.)
    A2 Elementary

    going a long way down from the surface or far into something.

    extending far downward from the top or surface, or far inward from the outer edge.

    Example

    The children were warned not to swim in the deep end of the pool.

    Example

    The divers explored a deep underwater cave that had remained untouched by humans for centuries.
  2. 2 serious or complex (adj.)
    B1 Intermediate

    showing great knowledge or serious thought that is not easy to understand.

    requiring or showing great intellectual depth or complexity; not superficial.

    Example

    They had a deep conversation about the meaning of life until late at night.

    Example

    The professor's lecture provided a deep analysis of the economic factors that led to the industrial revolution.
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  1. 3 sound or colour (adj.)
    B1 Intermediate

    describing a low sound or a dark, strong colour.

    low in pitch or frequency; having high saturation and low lightness in colour.

    Example

    He has a very deep voice that carries across the room.

    Example

    She wore a dress of deep red velvet that shimmered under the ballroom lights.
  2. 4 intense sleep (adj.)
    B1 Intermediate

    a state of sleep that is very difficult to wake up from.

    referring to a state of heavy, profound sleep characterized by low responsiveness to external stimuli.

    Example

    I was in such a deep sleep that I didn't hear the thunderstorm.

    Example

    After the exhausting hike, the entire group fell into a deep sleep before the sun had even set.
  3. 5 to a great depth (adv.)
    B1 Intermediate

    far down or far into something.

    to a significant depth or distance inward; often used figuratively to describe involvement.

    Example

    You need to breathe in deep before you start the exercise.

    Example

    The roots of the ancient oak tree reach deep into the soil to find water during the dry summer months.
  4. 6 the ocean (n.)
    B2 Upper Intermediate Literary

    the deepest part of the sea or ocean.

    the most profound or central part of a body of water or a period of time; often used with 'the'.

    Example

    Strange creatures live in the dark silence of the deep.

    Example

    The sailors told legends of giant monsters that rose from the deep to swallow entire ships.
  5. 7 to overthink (v.)
    C1 Advanced Slang British English

    to think about something too much or take it too seriously.

    to consider something with excessive gravity or to overanalyse a situation.

    Example

    Don't deep it too much; he probably just forgot to reply to your text.

    Example

    I started to deep the situation and realized I might have overreacted during our meeting yesterday.
Origin

From Middle English depe, deep, dep, deop, from Old English dēop (“deep, profound; awful, mysterious; heinous; serious, solemn, earnest; extreme, great”), from Proto-West Germanic deup, from Proto-Germanic deupaz (“deep”), from Proto-Indo-European dʰewbʰ-nós, from dʰewbʰ- (“deep”). Cognates Cognate with Scots depe (“deep”), North Frisian diip, jip (“deep”), Saterland Frisian djoop (“deep”), West Frisian djip (“deep”), Alemannic German tüüf (“deep”), Central Franconian deef, deep (“deep”), Dutch diep (“deep”), German tief (“deep”), Luxembourgish déif (“deep”), Mòcheno tiaf (“deep”), Vilamovian tif, tīf, tiif (“deep”), Yiddish טיף (tif, “deep”), Danish dyb (“deep”), Faroese, Icelandic djúpur (“deep”), Norwegian Bokmål djup, dyp (“deep”), Norwegian Nynorsk, Swedish djup (“deep”), Scanian djyber (“deep”), Gothic 𐌳𐌹𐌿𐍀𐍃 (diups, “deep”), Lithuanian dubùs (“deep, hollow”), Albanian det (“sea”), Welsh dwfn (“deep”).

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