Definitions for "Roller coaster"
An amusement railroad of varying design in which open cars coast by gravity over a long winding track in a closed circuit, with steep pitches and ascents, and in some cases loops in which the cars are briefly upside-down; typically, the cars are pulled by a chain device to the top of the first peak, after which gravity and momentum provide the only propulsive forces. In some cases, the cars are suspended from a monorail rather than resting on a track, and such cars may be made to swing outward at an angle near to the horizontal. It is a popular amusement at many amusement parks, but is sufficiently frightening to some people that they refuse to ride in one.
anything characterized by abrupt and extreme changes (especially up and down); "the economy has been on a roller coaster all year"
elevated railway in an amusement park (usually with sharp curves and steep inclines)
Keywords:  slump, gain
a slump after a gain.
Keywords:  newton, motion, laws, good, example
a good example of more than one of Newton's laws of motion
Keywords:  imitated, theory, eight, ten, musical
A musical change, 3216549870. While in theory it only exists on ten, it is often imitated, with 14327658 on eight.
a prime example of the energy principle, where the potential energy provided as you pass the highest point is all you have to take you round the track
Keywords:  gravity, train, powered
a gravity-powered train
Keywords:  sensation, safety, balance
a balance between safety and sensation