deep vs slack

deep

• The deep part of a lake, sea, etc. 

• A deep hole or pit, a water well; an abyss. 

• A deep shade of colour. 

• A silent time; quiet isolation. 

• The profound part of a problem. 

• A fielding position near the boundary. 

• The sea, the ocean. 

• In a (specified) number of rows or layers. 

• Positioned or reaching far, especially down through something or into something. 

• Voluminous. 

• Far in extent in another (non-downwards, but generally also non-upwards) direction away from a point of reference. 

• Low in pitch. 

• Far from the center of the playing area, near to the boundary of the playing area, either in absolute terms or relative to a point of reference. 

• Distant in the past, ancient. 

• Significant, not superficial, in extent. 

• Muddy; boggy; sandy; said of roads. 

• Extending far down from the top, or surface, to the bottom, literally or figuratively. 

• Penetrating a long way, especially a long way forward. 

• Hard to penetrate or comprehend; profound; intricate; obscure. 

• Positioned back, or downfield, towards one's own goal, or towards or behind one's baseline or similar reference point. 

• Thick. 

• Profound, having great meaning or import, but possibly obscure or not obvious. 

• Extending to a level or length equivalent to the stated thing. 

• Highly saturated; rich. 

• Sound, heavy (describing a state of sleep from which one is not easily awoken). 

• Of penetrating or far-reaching intellect; not superficial; thoroughly skilled; sagacious; cunning. 

• In a profound, not superficial, manner. 

• In large volume. 

• Back towards one's own goal, baseline, or similar. 

• Far, especially far down through something or into something, physically or figuratively. 

slack

• A tidal marsh or shallow that periodically fills and drains. 

• Unconditional listening attention given by client to patient. 

• A temporary speed restriction where track maintenance or engineering work is being carried out at a particular place. 

• The part of anything that hangs loose, having no strain upon it. 

• Small coal; coal dust. 

• A valley, or small, shallow dell. 

• To slacken. 

• To lose cohesion or solidity by a chemical combination with water; to slake. 

• Moderately warm. 

• Vulgar; sexually explicit, especially in dancehall music. 

• Not active or busy, successful, or violent. 

• Excess; surplus to requirements. 

• Lax; not tense; not firmly extended. 

• Lacking diligence or care; not earnest or eager. 

• Lax. 

• Moderate in speed. 

• Weak; not holding fast. 

• Slackly.