Definitions
01far down or in
A2 · Elementary
adj. going a long way down from the surface or far into something.
adj. extending far downward from the top or surface, or far inward from the outer edge.
“The children were warned not to swim in the deep end of the pool.”
“The divers explored a deep underwater cave that had remained untouched by humans for centuries.”
Synonyms
Antonyms
02serious or complex
B1 · Intermediate
adj. showing great knowledge or serious thought that is not easy to understand.
adj. requiring or showing great intellectual depth or complexity; not superficial.
“They had a deep conversation about the meaning of life until late at night.”
“The professor's lecture provided a deep analysis of the economic factors that led to the industrial revolution.”
Synonyms
Antonyms
03sound or colour
B1 · Intermediate
adj. describing a low sound or a dark, strong colour.
adj. low in pitch or frequency; having high saturation and low lightness in colour.
“He has a very deep voice that carries across the room.”
“She wore a dress of deep red velvet that shimmered under the ballroom lights.”
04intense sleep
B1 · Intermediate
adj. a state of sleep that is very difficult to wake up from.
adj. referring to a state of heavy, profound sleep characterized by low responsiveness to external stimuli.
“I was in such a deep sleep that I didn't hear the thunderstorm.”
“After the exhausting hike, the entire group fell into a deep sleep before the sun had even set.”
Antonyms
05to a great depth
B1 · Intermediate
adv. far down or far into something.
adv. to a significant depth or distance inward; often used figuratively to describe involvement.
“You need to breathe in deep before you start the exercise.”
“The roots of the ancient oak tree reach deep into the soil to find water during the dry summer months.”
Synonyms
06the ocean
B2 · Upper Intermediate Uncountable noun Literary
n. the deepest part of the sea or ocean.
n. the most profound or central part of a body of water or a period of time; often used with 'the'.
“Strange creatures live in the dark silence of the deep.”
“The sailors told legends of giant monsters that rose from the deep to swallow entire ships.”
07to overthink
C1 · Advanced Slang · British English
v. to think about something too much or take it too seriously.
v. to consider something with excessive gravity or to overanalyse a situation.
“Don't deep it too much; he probably just forgot to reply to your text.”
“I started to deep the situation and realized I might have overreacted during our meeting yesterday.”
Real-World Examples
“The deeper you dive, for example, the faster gasses get pushed into your tissues, which imposes limits on these really deep dives.” “A sensors-driven robotic platform maintains in situ deep-sea conditions from ocean sampling to laboratory cultivation systems, enabling the successful isolation and characterization of bacteria from the deep ocean.” “In 1997, for instance, bacteria were found as deep as 2.8km (1.7 miles) deep inside a gas borehole.” “Operating 24 hours a day for the last six weeks, researchers subjected cameras and other equipment to extreme water pressure, recording as deep as 6,000m (19,700ft).” Etymology
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”).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
VERB
ADJECTIVE
ADVERB
Related words
Idioms
01. deep cut
02. deep down
03. deep pockets
04. deep six
05. deep thinker
06. deep water
07. dig deep
09. in deep
10. in too deep
Domains
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.A2 KeyIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.3.0–4.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 2.0–2.524–43TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.225–549
- Frequency
- Very common
- Level
- A2 · ElementaryOxford
- Updated
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「カタカナ語」 data: JMdict (EDRDG), CC BY-SA 4.0