1. adjective /diːp/
That is a deep thought!
I just meant to help out a little, but now Im deep into it.
Syn: heavy, meaningful, profound, far, thick, great, large, voluminous, low, low-pitched, bright, rich, vivid
Ant: shallow, frivolous, light, superficial, thin, small, high, high-pitched, piping, pale, desaturated, washed-out
2. adverb /diːp/
Hepaticology, outside the temperate parts of the Northern Hemisphere, still lies deep in the shadow cast by that ultimate "closet taxonomist," Franz Stephani—a ghost whose shadow falls over us all.
3. noun /diːp/
a) (meaning 1 above) part of a lake, sea, etc.
creatures of the deep
b) The deep (meaning 2 above) part of a problem.
Russell is a safe pair of hands in the deep
See Also: ankle-deep, beauty is only skin deep, deep background, deep blue sea, deep copy, deepen, deep down, deep drawing, deep end, deep fat, deep-fet, deep-freeze, deep freezer, deep-fry, deep in the money, deep in thought, deep kiss, deep-kiss, deep-laid, deep link, deep-mouthed, deep out of the money, deep pockets, deep-read, deap sea, deep-sea, deep-seated, deep-set, deep-six, Deep South, deep space, deep structure, deep supporting fire, Deep Thought, Deep Throat, deepthroat, deep vein thrombosis, DVT, deep web, deep well, depth, in too deep, knee-deep, neck-deep, skin-deep, still waters run deep, waist-deep
Wikipedia foundation.