Longman Dictionary of Contemporary English - revolution

~ n 1 a complete change in ways of thinking, methods of working etc  (Computer technology has caused a revolution in business practices.)  (- see also industrial revolution) 2 a time of great, usually sudden, social and political change, especially the changing of a ruler or political system by force  (the French Revolution | social inequalities that led to revolution)  (- see also counter­revolution) 3 one complete circular movement, or continued circular movement, around a fixed point + round/around  (The Earth makes one revolution round the sun each year.) 4 one complete circular spinning movement, made by something such as a wheel fixed on a central point  (a speed of 100 revolutions per minute)  (- see also revolve)