Word forms: roller-coasters
1. countable noun A roller-coaster is a small railway at a fair that goes up and down steep slopes fast and that people ride on for pleasure or excitement. big dipper ⇒ It's great to go on the roller coaster five times and not be sick. 2. countable noun [usu sing] If you say that someone or something is on a roller coaster, you mean that they go through many sudden or extreme changes in a short time. [journalism] ⇒ I've been on an emotional roller-coaster since I've been here. ⇒ Over the last few years Japan's socialists have seen their electoral popularity take a roller-coaster ride.
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