verb (used with object) 1.to decrease the velocity of: He decelerates the bobsled when he nears a curve.
2.to slow the rate of increase of: efforts to decelerate inflation.
verb (used without object) 3.to slow down: The plane decelerated just before landing.
Related forms de·cel·er·a·tion, noun
de·cel·er·a·tor, noun
non·de·cel·er·a·tion, noun