retarder
retarder — noun
1. a person, condition, or element that causes something to happen more slowly than
a person, condition, or element that causes something to happen more slowly than expected, or prevents it from moving forward at a normal pace.
The manager was seen as a retarder of innovation, refusing to approve new software tools.
retarder of + [abstract noun] — shows what is being delayed
Traffic jams act as a major retarder of economic activity in large cities.
The lack of funding was the biggest retarder of the hospital expansion project.
Outdated government rules can serve as a retarder of scientific research by blocking new studies.
- obstacle
more general and widely used; fits any context from physical to abstract
- hindrance
similar in formality, but emphasises an active blocking effect
- bottleneck
specific to a point in a process where flow is restricted
- impediment
slightly more formal; often suggests a lasting barrier
- accelerator
something that speeds up progress or development
- catalyst
something that causes activity or change to happen faster
文法句型
retarder of + noun phrase
用法筆記
Frequently used in formal or analytical writing rather than in everyday speech. When applied to a person, this word may be perceived as harsh or judgmental; in most contexts it is more natural to describe the person's actions (e.g., 'He is slowing progress') rather than using a noun label.
常見錯誤
2. a chemical additive that is mixed into a material such as concrete, plaster, or
a chemical additive that is mixed into a material such as concrete, plaster, or rubber to make it harden or set more slowly than it normally would.
The crew added a retarder to the concrete to stop it from setting too fast.
add a retarder to [material] — typical construction usage
Diego mixed a retarder into the plaster to give more time for shaping the ceiling.
In hot weather, concrete mixed without a retarder can begin to harden within minutes.
Baraka tested different amounts of retarder to find the right curing speed for the rubber.
Adina explained that a plaster retarder is essential when working on large decorative ceiling moulds.
- inhibitor
broader term used in chemistry; can also mean a substance that stops a reaction entirely
- stabilizer
keeps a material in a steady state rather than just slowing its change
- retardant
closest synonym, often used interchangeably (e.g., 'fire retardant'), though 'retardant' is more common as an adjective
- accelerator
a substance that speeds up the setting or curing process
文法句型
retarder + noun (modifier)
add a retarder to + noun
retarder for + material
用法筆記
Commonly used in construction, materials science, and manufacturing contexts. The specific material is often named in a compound noun (e.g., 'concrete retarder', 'gypsum retarder', 'rubber retarder'). Uncountable when referring to the substance in general ('Retarder is added to the mix'); countable when referring to types or brands ('This retarder works better than that one').
常見錯誤
3. a mechanical or hydraulic braking device installed along railway tracks that red
a mechanical or hydraulic braking device installed along railway tracks that reduces the speed of freight cars as they roll into a classification yard or siding.
The retarder on the track slowed the freight car before the siding ended.
retarder on [track/siding] — shows location on railway infrastructure
Darius watched the yard operator activate the retarder to slow the rolling cars.
activate the retarder — verb + noun collocation
A faulty retarder caused two wagons to collide at the bottom of the hump.
Trang learned to maintain the hydraulic retarder as part of her railway training course.
- track brake
a more general term for any braking device mounted on rails
- decelerator
rare in railway contexts; more common in physics and automotive engineering
文法句型
retarder on + noun (track/siding)
retarder + noun (modifier)
activate/operate the retarder
用法筆記
Almost exclusively used in railway engineering and operations. Retarders are typically found in hump yards (classification yards built on a slope) where freight cars roll downhill and must be slowed before coupling. The device may be operated manually or by computer.