Meanings
present singular third person decelerates · participle present decelerating · participle past decelerated · past decelerated
- transitiveTo reduce the velocity of something.
The S.D.R. [Somerset & Dorset Railway] could not adhere to this schedule, and had to decelerate the service, but the original timings were restored when the M.R. and L.S.W.R. leased the S.D.R.
1953 August, David R. Webb, “By Rail to Bournemouth”, in Railway Magazine, page 5541 more example
In May, for example, the Illinois Central RR. introduced the long-expected streamline version of the Panama Limited, with diesel haulage, cutting the time over the 921 miles between Chicago and New Orleans by 2hr. to 18hr. each way—the fastest on record—but decelerated other trains over the same route.
1942 November and December, “Notes and News: The War and American Train Services”, in Railway Magazine, page 369 - intransitiveTo go slower.
1 more example
One of the disadvantages of increasing intermediate stops is that, as we have pointed out already, certain prestige trains have to suffer, notably the "Cornish Riviera Express", slowed 15min to Plymouth by stops at Taunton and Exeter; the "Torbay Express", decelerated 18min by stops at Reading, Westbury, Taunton and Newton Abbot; and the "Bristolian", which adds 14min in order to allow for a Bath stop and an increased load.
1961 October, “The winter timetables of British Railways: Western Region”, in Trains Illustrated, page 590
Synonyms & antonyms
verbTo reduce the rate of advancement of something, such as a disease.
More synonyms by meaning
verblose velocity; move more slowly
Synonym sets from Open English WordNet, CC BY 4.0.
Origin
Late 19th c., from de- + (ac)celerate. Compare deaccelerate.
Full word history & related roots →Translations
Arabic أبْطَأ, تَبَاطَأ
- أبْطَأreduce the velocity of something
- تَبَاطَأ (tabāṭaʔ)reduce the velocity of something
- تَبَاطَأ (tabāṭaʔ)to go slower
Bulgarian намалявам скоростта, намалявам скоростта
- намалявам скоростта (namaljavam skorostta)reduce the velocity of something
- намалявам скоростта (namaljavam skorostta)reduce the rate of advancement of something
- забавям (zabavjam)to go slower
Catalan descelerar, desaccelerar
- descelerarreduce the velocity of something
- desaccelerarreduce the velocity of something
- descelerarreduce the rate of advancement of something
- desaccelerarreduce the rate of advancement of something
Czech zpomalit
- zpomalitto go slower
Finnish hiljentää vauhtia, hidastaa
- hiljentää vauhtiareduce the velocity of something
- hidastaareduce the velocity of something
- hidastaareduce the rate of advancement of something
- hidastuato go slower
French ralentir, décélérer
- ralentirreduce the velocity of something
- décélérerreduce the velocity of something
- ralentirto go slower
- décélérerto go slower
Hungarian lassít, lelassít
- lassítreduce the velocity of something
- lelassítreduce the velocity of something
- lassulto go slower
- lelassulto go slower
Italian decelerare, decelerare
- decelerarereduce the velocity of something
- decelerareto go slower
Latin retardare, retardare
- retardarereduce the velocity of something
- retardarereduce the rate of advancement of something
Māori whakapōturi, whakapūhoi
- whakapōturireduce the velocity of something
- whakapūhoito go slower
Polish zwalniać, zwolnić
- zwalniaćreduce the velocity of something
- zwolnićreduce the velocity of something
- spowalniaćreduce the velocity of something
- spowolnićreduce the velocity of something
- zwalniaćreduce the rate of advancement of something
- zwolnićreduce the rate of advancement of something
- spowalniaćreduce the rate of advancement of something
- spowolnićreduce the rate of advancement of something
- zwalniaćto go slower
- zwolnićto go slower
- spowalniaćto go slower
- spowolnićto go slower
Romanian încetini, încetini
- încetinireduce the velocity of something
- încetinireduce the rate of advancement of something
- încetinito go slower
- decelerato go slower
Russian замедля́ть, заме́длить
- замедля́ть (zamedljátʹ)reduce the velocity of something
- заме́длить (zamédlitʹ)reduce the velocity of something
- замедля́ться (zamedljátʹsja)to go slower
- заме́длиться (zamédlitʹsja)to go slower
Spanish desacelerar, decelerar
- desacelerarreduce the velocity of something
- decelerarreduce the velocity of something
- desacelerarto go slower
- decelerarto go slower
Tagalog hidarasigin
- hidarasiginreduce the velocity of something
Ukrainian спові́льнювати, спові́льнити
- спові́льнювати (spovílʹnjuvaty)reduce the velocity of something
- спові́льнити (spovílʹnyty)reduce the velocity of something
- спові́льнюватися (spovílʹnjuvatysja)to go slower
- спові́льнитися (spovílʹnytysja)to go slower
Cite this entry
decelerate. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/decelerate
“decelerate.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/decelerate. Accessed November 2, 2026.
WatkinsX Dictionary, s.v. “decelerate,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/decelerate.
Source: decelerate on Wiktionary, CC BY-SA 4.0.