Simple past tense and past participle of decelerate.(verb)
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Use "decelerated" in a sentence
"Growth decelerated from the second quarter, when the economy expanded 1.4% on quarter."
""It kind of decelerated rather than accelerated," says Mr. Luczo, in an interview."
"The technical annexe to the HS2 report quietly admits that Coventry, for instance, will have its fast London service slashed by two-thirds, from three trains an hour to one, and "decelerated" by at least 10 minutes."