deep (adj.)

Old English deop "having considerable extension downward," especially as measured from the top or surface, also figuratively, "profound, awful, mysterious; serious, solemn," from Proto-Germanic *deupaz (source also of Old Saxon diop, Old Frisian diap, Dutch diep, Old High German tiof, German tief, Old Norse djupr, Danish dyb, Swedish djup, Gothic diups "deep"), from PIE root *dheub- "deep, hollow" (source also of Lithuanian dubus "deep, hollow," Old Church Slavonic duno "bottom, foundation," Welsh dwfn "deep," Old Irish domun "world," via sense development from "bottom" to "foundation" to "earth" to "world").

By early 14c. "extensive in any direction analogous to downward," as measured from the front. From late 14c. of sound, "low in pitch, grave," also of color, "intense." By c. 1200, of persons, "sagacious, of penetrating mind." From 1560s, of debt., etc., "closely involved, far advanced."

Deep pocket as figurative of wealth is from 1951. To go off the deep end "lose control of oneself" is slang recorded by 1921, probably in reference to the deep end of a swimming pool, where a person on the surface can no longer touch bottom. When 3-D films seemed destined to be the next wave and the biggest thing to hit cinema since talkies, they were known as deepies (1953)., hard to understand

deep (n.)

Old English deop "deep water," especially the sea, from the source of deep (adj.). Cognate with Old High German tiufi, German Tief, Teufe, Dutch diep, Danish dyb. General sense of "that which is of great depth" is by mid-14c.

deep (adv.)

"far down, deeply," Old English deope, from the source of deep (adj.).

updated on December 05, 2018

Definitions of deep from WordNet
deep (adj.)
relatively deep or strong; affecting one deeply;
in a deep sleep
a deep trance
a deep breath
deep concentration
a deep sigh
deep emotion
deep (adj.)
marked by depth of thinking;
deep thoughts
a deep allegory
deep (adj.)
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;
deep shelves
a deep gash
deep water
in deep space
a deep well
deep pressure receptors in muscles
a deep closet
a deep casserole
hit the ball to deep center field
a deep dive
surrounded by a deep yard
deep massage
deep (adj.)
very distant in time or space;
deep in the past
deep in enemy territory
a deep space probe
deep in the woods
deep (adj.)
intense or extreme;
deep happiness
in deep trouble
deep (adj.)
having or denoting a low vocal or instrumental range;
a deep voice
Synonyms: bass
deep (adj.)
strong; intense;
deep purple
Synonyms: rich
deep (adj.)
relatively thick from top to bottom;
deep snow
deep carpets
deep (adj.)
extending relatively far inward;
a deep border
deep (adj.)
(of darkness) densely dark;
a face in deep shadow
deep night
Synonyms: thick
deep (adj.)
large in quantity or size;
deep cuts in the budget
deep (adj.)
with head or back bent low;
a deep bow
deep (adj.)
of an obscure nature; "in its mysterious past it encompasses all the dim origins of life"- Rachel Carson;
a deep dark secret
Synonyms: cryptic / cryptical / inscrutable / mysterious / mystifying
deep (adj.)
difficult to penetrate; incomprehensible to one of ordinary understanding or knowledge;
a deep metaphysical theory
Synonyms: abstruse / recondite
deep (adj.)
exhibiting great cunning usually with secrecy;
deep political machinations
a deep plot
deep (n.)
the central and most intense or profound part;
in the deep of night
in the deep of winter
deep (n.)
a long steep-sided depression in the ocean floor;
Synonyms: trench / oceanic abyss
deep (n.)
literary term for an ocean;
denizens of the deep
deep (adv.)
to a great depth; far down or in;
dug deep
Synonyms: deeply
deep (adv.)
to an advanced time;
deep into the night
Synonyms: late
deep (adv.)
to a great distance;
penetrated deep into enemy territory
went deep into the woods
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