proof
/pruːf/ (bre, ipa) · /pruːf/ (ame, ipa) · /ˈprüf/ (ame, mw) · /-pruːf/ (bre, ipa) · /-pruːf/ (ame, ipa)
proof — noun
1. facts or documents that establish beyond doubt that a particular claim is true o
facts or documents that establish beyond doubt that a particular claim is true or that a given situation exists
The police found proof that Noa had been at the bank that morning.
proof + that-clause for factual certainty
Scientists are still searching for proof of ancient life on the red planet.
proof of + noun phrase
Do you have any proof that the car was damaged before you bought it?
The signed contract served as proof that both sides had accepted the terms.
- evidence
wider term; evidence suggests something may be true, while proof aims to establish it beyond doubt
- confirmation
focuses on verifying something already suspected or known
- verification
more formal; often used in scientific or technical contexts
- disproof
formal term for evidence that shows something is false
文法句型
proof + that-clause
proof of + noun phrase
用法筆記
Uncountable in most contexts ('We need proof'), but countable when referring to specific documents or pieces of evidence ('She collected several proofs of her identity').
常見錯誤
2. a formal chain of reasoning that confirms the correctness of a mathematical clai
a formal chain of reasoning that confirms the correctness of a mathematical claim or scientific proposition
The mathematician published her proof of the theorem in a leading journal.
proof of + abstract concept
Students had to write a complete proof for each geometry problem on the exam.
complete / write a proof
The professor checked Joon's proof and confirmed that every step was valid.
For his doctoral thesis, Darius developed an original proof that surprised the mathematics department.
- demonstration
broader term; can refer to showing how something works, not just logical reasoning
- argument
less formal; may not have the same rigor as a mathematical proof
用法筆記
Countable — you can say 'a proof' or 'proofs' in this sense. Unlike sense 1, this refers to a structured logical argument rather than general evidence.
3. an early printed version of a book or article that writers and editors examine a
an early printed version of a book or article that writers and editors examine and correct prior to the production of the finished publication
The editor sent the proof back to the printer with several corrections marked in red.
send a proof back for corrections
Stephanie was asked to check the page proofs of her novel before the deadline.
page proofs (compound noun)
The designer spotted a spelling mistake on the galley proof that everyone else had missed.
The page proof revealed a typo in the chart that would have confused readers if it went uncorrected.
- galley proof
a specific type of early proof, usually in a single column before page layout
- page proof
a proof arranged in final page format
用法筆記
Common in publishing and journalism. Related verbs are 'proofread' (to check proofs) and 'proof' (to make something waterproof — a different sense).
常見錯誤
4. a system of measuring how much alcohol is in a drink, where a higher number mean
a system of measuring how much alcohol is in a drink, where a higher number means stronger alcohol; in the US, 100 proof equals 50% alcohol by volume
This bottle of bourbon is 80 proof, which is standard for most whiskeys.
number + proof (measurement phrase)
The bartender warned that 100 proof rum is much stronger than the usual kind people mix with cola.
Paloma asked the clerk if the 151 proof rum was too strong for mixing margaritas.
Romi checked the label and saw that the whisky was 120 proof, the highest she had ever seen.
用法筆記
The US and UK systems differ slightly. In the UK, proof historically referred to a specific gravity test, but modern labeling uses alcohol-by-volume (ABV) instead. In everyday US conversation, the proof number is simply double the ABV percentage.
proof — adjective
1. having a specified level of alcohol expressed in proof units, where larger numbe
having a specified level of alcohol expressed in proof units, where larger numbers indicate drinks that contain more alcohol
Lin bought a bottle of 60 proof vodka for mixing light cocktails at the party.
number + proof + beverage (adjective before noun)
At the party, Bao noticed the coffee liqueur was only 30 proof, much milder than the whiskey.
Kabir poured his friend a glass of 100 proof bourbon, praising its rich smoky flavor.
Asher picked a low-proof coffee liqueur for the tiramisu to add flavor without the alcohol taste.
文法句型
always after a number: '60 proof whiskey'
用法筆記
Always comes immediately after a number and before the noun it modifies. Never used alone as an adjective ('a proof whiskey'). The US proof number is always double the alcohol-by-volume percentage.
常見錯誤
2. designed to withstand or hold out against a specific damaging force, including w
designed to withstand or hold out against a specific damaging force, including water, fire, impact, or pressure
The new winter jacket is proof against heavy rain and freezing wind.
proof against [weather]
No electronic safe is completely proof against a determined thief with the right tools.
The mountain shelter was built to be proof against the worst storms the region could produce.
The new phone case is advertised as proof against drops from up to two meters high.
- resistant
broader term; can describe partial resistance rather than complete protection
- impervious
more formal; suggests nothing can get through at all
- vulnerable
open to damage or attack
文法句型
proof against + noun phrase
用法筆記
This sense is being gradually replaced by the more common '-proof' suffix (waterproof, fireproof, bulletproof). 'Proof against' sounds more formal and is often used in technical or literary contexts.
常見錯誤
proof — verb
1. to apply a special substance to a surface such as fabric, wood, or walls so that
to apply a special substance to a surface such as fabric, wood, or walls so that water or other liquids cannot pass through
Théo proofed the wooden deck with a clear sealant before the rainy season began.
proof + surface with [substance]
The basement walls were proofed against moisture before the new flooring was installed.
passive: proofed against [threat]
Vivek sprayed each canvas roll with a sealant to proof it against heavy rain.
Before installing the shower, the contractor proofed the wall tiles with a waterproof membrane.
- waterproof
more common everyday verb; 'proof' is shorter and more technical
- seal
broader term; can mean closing gaps without implying a special coating
文法句型
proof + noun phrase (object)
proof + object + against + noun
用法筆記
Distinct from 'proofread' (to check text for errors). This verb is mainly used in construction, outdoor gear, and fabric treatment contexts.
常見錯誤
proof — suffix
1. added to nouns to form adjectives meaning that something cannot be damaged, harm
added to nouns to form adjectives meaning that something cannot be damaged, harmed, or penetrated by the thing named; for example, 'waterproof' means water cannot get through, and 'bulletproof' means bullets cannot go through
Marta bought a waterproof phone case for her trip to the beach.
waterproof (most common -proof compound)
The bank teller sat behind a bulletproof glass window all day.
bulletproof glass (compound noun)
The bakery uses greaseproof paper to line its baking trays so the cookies do not stick.
The new apartment complex has fireproof doors in every hallway for safety.
文法句型
[noun] + proof = adjective
用法筆記
This is a highly productive suffix in English. New compounds are constantly being created, especially in marketing (e.g., 'wrinkle-proof,' 'scratch-proof'). The resulting adjective cannot usually be compared ('more waterproof' is rare).