invalid
invalid — adjective
1. used to describe a document, ticket, law, or agreement that has no legal force b
used to describe a document, ticket, law, or agreement that has no legal force because it does not follow the required rules.
Élise's passport was declared invalid because it had expired three months earlier.
passive: be declared invalid
The court ruled that the old contract was invalid and could not be enforced.
ruled + that-clause + invalid
Owen tried to use a discount coupon, but the shop assistant said it was invalid.
Any signature made under threat is considered invalid under state law.
Voters who arrived late were told their ballots would be invalid.
- valid
the direct opposite; legally or officially acceptable
用法筆記
Frequently used in passive constructions with verbs like 'declare,' 'rule,' and 'consider.' The object is typically a legal or official document (passport, contract, ballot).
常見錯誤
2. used to describe an argument, reason, or opinion that is wrong because it is bui
used to describe an argument, reason, or opinion that is wrong because it is built on faulty reasoning or incorrect facts.
Lien's argument was invalid because it assumed a cause without offering any evidence.
argument + be + invalid + because-clause
The professor pointed out that the student's reasoning was invalid from the start.
pointed out + that-clause + reasoning + be + invalid
Eli's conclusion is invalid since it does not follow from the facts presented.
The logic of that proposal falls apart because its main premise is invalid.
- unsound
suggests the reasoning has a hidden weakness; slightly more formal
- fallacious
implies a recognizable error in logic; quite formal
- flawed
softer than invalid; suggests a mistake rather than complete wrongness
用法筆記
Common with nouns of reasoning: 'argument,' 'reasoning,' 'conclusion,' 'premise.' Distinguish from sense 1 (NOT LEGALLY ACCEPTABLE): sense 2 deals with logical flaws, not legal standing.
invalid — noun
1. a person who is weak or ill over a long period and relies on others for daily ca
a person who is weak or ill over a long period and relies on others for daily care.
The nurse visited the old invalid every morning to bring his medicine.
old invalid (common modifier pair)
After the stroke, Hiro's grandmother became an invalid and needed help with everything.
became an invalid (change-of-state pattern)
The charity delivers hot meals to invalids who cannot leave their homes.
When Reema was bedridden, she hated being treated like an invalid.
用法筆記
Considered old-fashioned and potentially offensive in modern usage. Alternatives such as 'person with a disability' or 'person living with a chronic illness' are now preferred.
常見錯誤
invalid — verb
1. to officially release a member of the armed forces or emergency services from du
to officially release a member of the armed forces or emergency services from duty because they are too sick or injured to continue serving.
The army invalided Sergeant Obi after he lost his hearing during combat training.
army + invalid + [person] after [event]
Firefighters who are badly injured may be invalided out of the service.
passive: be invalided out of + service
Christopher was invalided home after developing a severe lung infection.
The navy invalided two officers who were hurt during the training exercise.
- discharge
general term for releasing someone from service; does not imply a medical reason
- muster out
American English term for formal military discharge
文法句型
invalid + somebody + out of/from + service
用法筆記
Predominantly British English, especially in military contexts. The American equivalent is usually 'discharged for medical reasons.' Often used in the passive voice or with the particle 'out.'
2. to make a person permanently weak, sick, or unable to move normally, especially
to make a person permanently weak, sick, or unable to move normally, especially through injury or disease.
The car accident invalided Mauricio and left him unable to walk properly.
accident + invalid + [person] (cause—result pattern)
A childhood illness invalided Camille and confined her to a wheelchair.
The disease invalided several soldiers before a cure was found.
A workplace accident invalided Benjamin and ended his career as a builder.
文法句型
invalid + somebody
用法筆記
Very rare in modern English; 'disabled' or 'left disabled' are far more common. Distinguish from verb sense 1 (REMOVE FROM DUTY): sense 1 is about administrative removal from service, while sense 2 describes the physical act of causing disability.