fast reactor
C2Technical/Specialized
Definition
Meaning
A nuclear reactor that uses fast neutrons to sustain its fission chain reaction, as opposed to thermal (slow) neutrons.
A type of nuclear reactor technology that operates without a neutron moderator, allowing for more efficient fuel use and the potential to generate more fissile material than it consumes (breeding).
Linguistics
Semantic Notes
The term is a compound noun where 'fast' specifically refers to the high kinetic energy of the neutrons, not the speed of the reactor's operation. It is a hypernym for specific designs like 'breeder reactor' or 'sodium-cooled fast reactor'.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences. The term is identical in both varieties. Pronunciations of the constituent words may follow regional patterns.
Connotations
Associated with advanced nuclear research, energy policy debates, and non-proliferation discussions in both regions.
Frequency
Equally low-frequency and highly specialized in both. Slightly more public discourse in the UK due to historical projects like the Dounreay Fast Reactor.
Vocabulary
Collocations
Grammar
Valency Patterns
[The/Our/This] fast reactor [operates/uses/generates/breeds] [plutonium/electricity].They are [researching/developing/building] a [new/sodium-cooled] fast reactor.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Rare. Used in energy sector reports and investment discussions concerning next-generation nuclear technology.
Academic
Primary context. Used in physics, nuclear engineering, and energy policy papers and textbooks.
Everyday
Extremely rare. Would only appear in detailed news reports about nuclear energy.
Technical
Standard, precise term in nuclear engineering and reactor physics.
Examples
By Part of Speech
adjective
British English
- The fast-reactor programme received renewed funding.
- Fast-reactor technology is complex.
American English
- The fast reactor program received renewed funding.
- Fast reactor technology is complex.
Examples
By CEFR Level
- A fast reactor is a special kind of nuclear power plant.
- It uses a different scientific process than most reactors.
- Unlike conventional reactors, a fast reactor does not require a moderator to slow down neutrons.
- The main advantage of fast reactors is their more efficient use of nuclear fuel.
- The decommissioning of the prototype fast reactor posed significant technical challenges due to its sodium coolant.
- Proponents argue that fast reactor technology could drastically reduce the volume of long-lived radioactive waste.
- The integral fast reactor design, which incorporates on-site pyroprocessing, was conceived as a closed fuel cycle system.
- Critics of fast breeder reactors often cite proliferation risks associated with the plutonium they produce.
Learning
Memory Aids
Mnemonic
Think: 'FAST neutrons move FAST and don't need to be slowed down (moderated) to cause fission.'
Conceptual Metaphor
N/A - Highly technical term with literal meaning.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid translating 'fast' as 'быстрый' in the sense of 'quick operating'. The correct Russian equivalent is 'реактор на быстрых нейтронах' (РБН), where 'быстрых' refers to neutron speed.
- Do not confuse with 'rapid reactor' – this is not a standard term.
Common Mistakes
- Using 'fast' as an adverb (e.g., 'The reactor runs fast').
- Confusing it with a 'fusion reactor'.
- Pronouncing 'reactor' with the stress on the first syllable (RE-actor).
Practice
Quiz
What does the word 'fast' refer to in 'fast reactor'?
FAQ
Frequently Asked Questions
Not exactly. A 'breeder reactor' is a type of fast reactor designed to produce more fissile fuel than it consumes. 'Fast reactor' is the broader category.
They are more technologically complex, expensive to build, and have faced political and public relations challenges related to safety (e.g., coolant fires) and nuclear proliferation concerns.
Liquid metal, typically sodium, is a common coolant because it does not moderate (slow down) neutrons effectively and has excellent heat transfer properties.
In principle, yes. Some fast reactor designs can fission the long-lived actinides found in spent nuclear fuel from conventional reactors, reducing waste toxicity.