To go into a sharp, sustained, often uncontrollable descent or decline.
Of an aircraft: to go into a rapid, uncontrollable descent in a steep spiral.
A severe mental or emotional collapse; emotional breakdown.
Any sharp, sustained, often uncontrollable descent or decline.
The rapid, uncontrollable descent of an aircraft in a steep spiral.
To improve in condition or status.
To improve, usually applied to technology, generally by complete replacement of one or more components
To replace with something better.
To improve the equipment or furnishings of or services rendered to
To replace a program with a later version of itself, a version having a higher version number or marketed under a more recent product name.
An upward grade or slope.
An improvement
An improved component or replacement item, usually applied to technology
Up a slope or grade.