quantum
quantum — noun
1. a single, indivisible packet of a measurable physical property — most often ener
a single, indivisible packet of a measurable physical property — most often energy — that nature treats as a basic building block and cannot split into smaller pieces
Noor learned in class that a quantum of light is called a photon.
collocation: quantum of light
Mayumi's experiment measured the exact quantum of energy released by the atom.
collocation: quantum of energy
Sivan watched the needle jump each time the detector caught a single quantum of light.
Hiro showed that every quantum of ultraviolet light from the lamp carried exactly the same amount of energy.
- particle
refers to a physical piece of matter rather than a packet of energy; a photon is both a particle and a quantum of light
- photon
a specific type of quantum — the quantum of electromagnetic radiation; more concrete and narrower in meaning
- packet
an informal term that describes how a quantum behaves, but lacks the precise scientific definition
- continuum
a continuous, unbroken sequence without discrete units, opposite of the discrete nature of a quantum
文法句型
quantum of + noun
用法筆記
The plural form is quanta, not 'quantums'. This sense appears almost exclusively in physics contexts. Distinguish from noun sense 2 (a general portion or amount), which follows the same 'quantum of' pattern but has no physical or technical meaning.
常見錯誤
2. a small but definite amount of something abstract — such as truth, doubt, or com
a small but definite amount of something abstract — such as truth, doubt, or comfort — that is treated as a single portion in a particular situation
Shirin dug through the old newspaper archives and found a small quantum of truth in the 1985 report.
collocation: quantum of truth
Kwame felt a quantum of doubt when the committee voted to close the neighbourhood library.
collocation: quantum of doubt
Hui found a quantum of comfort in the warm letter from her grandmother.
When Arjun weighed the flour on his kitchen scale, he found a quantum of error in every measurement.
文法句型
quantum of + noun
用法筆記
Unlike noun sense 1, this sense is not a physics term — it works with abstract nouns (truth, doubt, comfort, hope). It typically appears in formal or literary writing, not everyday conversation.
常見錯誤
quantum — adjective
1. very large, important, or dramatic in effect — used to emphasise that a change o
very large, important, or dramatic in effect — used to emphasise that a change or improvement is sudden and far-reaching
Caio's Mandarin skills made a quantum leap after he lived in Taipei for a year.
collocation: quantum leap
The company saw a quantum improvement in sales after launching the new app.
collocation: quantum improvement
Eve described the new treatment as a quantum advance in cancer care.
The new high-speed train brought a quantum change in regional travel between cities.
- dramatic
more common in everyday English; less scientific in tone than quantum
- enormous
focuses on size rather than suddenness; quantum emphasises a leap rather than a gradual increase
- revolutionary
suggests a complete change in thinking; quantum can describe a single dramatic step within an existing framework
- gradual
slow and step-by-step, the opposite of the sudden leap implied by quantum
文法句型
quantum + noun (leap/jump/improvement/advance/change)
用法筆記
Always appears before the noun it modifies — never used predicatively (❌ 'The change was quantum'). The commonest expression by far is quantum leap; quantum improvement and quantum advance are less frequent but still natural.
常見錯誤
2. connected with quantum mechanics — the branch of physics that describes how atom
connected with quantum mechanics — the branch of physics that describes how atoms, electrons, and other tiny particles behave in ways that differ from the everyday world we can see
Asher is taking a course on quantum computing at the National Taiwan University.
collocation: quantum computing
Eitan read about quantum entanglement in his physics textbook last night.
collocation: quantum entanglement
Eliska's physics students built a small laser to see quantum theory at work.
The research team used quantum mechanics to design a faster computer chip.
- subatomic
refers specifically to objects smaller than an atom; quantum is broader and includes the theoretical framework
- atomic
relates to atoms rather than the subatomic particles described by quantum mechanics; also far less precise as a scientific label
- particle
as an adjective, particle physics overlaps with quantum physics but focuses on the particles themselves rather than their wave-like behaviour
- classical
in physics, classical refers to Newtonian mechanics, which describes the everyday macroscopic world using different rules from quantum mechanics
文法句型
quantum + noun (mechanics/theory/computing/field)
用法筆記
This is the commonest sense of quantum overall — far more frequent in everyday reading than the noun senses. It forms compound nouns with dozens of terms (quantum physics, quantum mechanics, quantum theory, quantum computing, quantum field, quantum entanglement, quantum cryptography). In popular media, quantum often signals 'cutting-edge science'.