deceleration
UK[ˌdiːsɛləˈreɪʃən]US[ˌdiːsɛləˈreɪʃən]
n
The act or process of moving slower or making something move slower; a reduction in speed.
Morpheme Breakdown
de
celer
ation
de
reverse
celer
speed
ation
noun suffix
Etymology
The word deceleration is a modern scientific formation built from classical Latin components. The core is the Latin adjective celer, meaning "swift," which descends from the Proto-Indo-European root kel-, "to drive, set in motion." The prefix de-, meaning "down from" or "reverse," was attached to negate or reverse the action. Combined with the noun-forming suffix -ation, the literal construction means "the process of reversing speed." This logical, morpheme-by-morpheme assembly in the 19th century gave English a precise technical term for the reduction of velocity, contrasting directly with its counterpart, acceleration.
Analysis
Structure: de (reverse) + celer (speed) + ation (noun suffix)
de: A Latin prefix meaning "down, away, off, reverse, undo." In this word, it indicates reversal or reduction.
celer: From Latin celer, meaning "swift, quick, fast." It is a direct substring of the English spelling.
ation: A noun-forming suffix of Latin origin (-ationem), indicating an action or process.
Examples
The car began a smooth deceleration as it approached the traffic light.
Engineers are studying the deceleration forces experienced by astronauts during re-entry.
A gradual economic deceleration is forecast for the coming quarter.