valid

valid — adjective

1. Something that is valid is based on facts, good reasons, or clear logic, so it c

1.adjectiveB1
Definition

Something that is valid is based on facts, good reasons, or clear logic, so it can be seriously considered or trusted.

Example

Xiu made several valid points during the team meeting about the new project.

valid + point (common noun collocation)

The teacher explained why his argument was not valid in the science report.

not valid (negation pattern)

Common collocations
  • valid point
  • valid argument
  • valid reason
  • valid concern
  • valid excuse
  • valid question
Synonyms
  • sound

    stronger than valid — implies the argument has both correct logic and true facts

  • reasonable

    focuses on fairness and common sense rather than formal logic

  • legitimate

    suggests acceptance within a social, legal, or moral system

Antonyms
  • invalid

    the direct opposite; not based on truth or reason

  • unreasonable

    not based on good sense or fair thinking

Grammar Patterns

valid + noun

not + valid

Usage Note

Commonly used with abstract nouns like point, argument, reason, excuse, concern, or question. Very frequent in negative structures — 'not valid' — when rejecting a claim or explanation.

Common Mistakes

I am valid to join the club.
I have a valid reason to join the club.
'Valid' describes the reason or argument, not the person. Do not use 'valid' directly after a person's name with 'be.'
This is a valid question for asking.
This is a valid question.
'Valid' already includes the idea of being acceptable; adding 'for asking' is redundant.

2. When a ticket, document, or official paper follows the rules of a system — usual

2.adjectiveA2
Definition

When a ticket, document, or official paper follows the rules of a system — usually within a set time limit — it is considered valid.

Example

Sirin's passport is still valid for another six months of international travel.

still valid + for + duration

You cannot board the train with a ticket that is no longer valid.

no longer valid (expiry pattern)

Common collocations
  • valid passport
  • valid ticket
  • valid visa
  • valid ID
  • valid coupon
  • valid membership
Synonyms
  • current

    more common for licences and memberships; suggests it has not expired

  • unexpired

    formal term focused on time; still within the allowed period

Antonyms
  • expired

    no longer valid because the time limit has passed

  • invalid

    not accepted by the system, often due to expiry or incorrect information

Grammar Patterns

valid + for [time period]

valid + until [date]

still valid

no longer valid

Usage Note

Subject is typically a ticket, passport, visa, ID card, coupon, subscription, membership, or licence. Frequently followed by 'for' (duration), 'until' (expiry date), or 'in' (location).

Common Mistakes

My passport is validate until next year.
My passport is valid until next year.
'Valid' is an adjective; 'validate' is a verb meaning to make something officially acceptable.
The ticket is valid for use in three months.
The ticket is valid for three months.
'For' already shows the time period; adding 'use in' is unnecessary.

3. A legal document, agreement, or action is valid when the law recognizes it as ha

3.adjectiveB2
Definition

A legal document, agreement, or action is valid when the law recognizes it as having full authority and binding power.

Example

The contract is valid only if both parties sign it in front of a witness.

valid + condition (only if)

Mauricio's will was declared valid by the judge after the court hearing.

passive: declared valid + by [authority]

Common collocations
  • valid contract
  • valid will
  • valid agreement
  • valid signature
  • valid marriage
  • valid under law
Synonyms
  • lawful

    broader term meaning allowed by law; not limited to documents and agreements

  • binding

    emphasises that a contract or promise must be followed

  • enforceable

    can be made effective by a court if one party does not obey

Antonyms
  • void

    having no legal force from the beginning, as if it never existed

  • null and void

    legal phrase meaning completely without legal effect

Grammar Patterns

legally valid

declared valid

valid under [law]

valid + only if [condition]

Usage Note

Subject is typically contract, will, marriage, agreement, signature, or legislation. Frequently passive — 'declared valid,' 'ruled valid,' 'held to be valid.' Common in formal legal writing and court contexts.

Common Mistakes

The agreement is valid in law.
The agreement is valid under the law.
'Under the law' or 'under [system] law' is the standard legal preposition; 'in law' is less idiomatic in this context.
This signature is validate by the lawyer.
This signature is validated by the lawyer.
Use the verb 'validate' (with '-ed') for the action of making something valid; 'valid' is an adjective describing the state.

Word family

Synonym discussion

Sense: adjective/1

Valid, sound, reasonable, legitimate, and justified all describe claims that have good reasons behind them, but they differ in emphasis. Valid focuses on internal logic — an argument that follows correct reasoning. Sound goes further, requiring both valid logic and true premises. Reasonable suggests the claim meets ordinary expectations of fairness or common sense, without needing formal proof. Legitimate stresses that the claim is allowed or recognised within a system — legal, social, or moral. Justified focuses on whether there are sufficient grounds for an action or belief, often in response to a specific criticism. For example: 'a valid theory' follows logical rules; 'a reasonable request' is fair and practical; 'a legitimate concern' is one the system acknowledges; 'a justified criticism' responds to a clear fault.

valid ↗sound ↗reasonable ↗legitimate ↗justified

Common collocations

Nouns

  • valid point
  • valid argument
  • valid reason
  • valid concern
  • valid passport
  • valid ticket
  • valid visa
  • valid contract
  • valid ID
  • valid signature
  • valid excuse

Adverbs

  • still valid
  • legally valid
  • perfectly valid
  • no longer valid
  • equally valid

Phrases

  • valid only if
  • valid for a period of
  • valid from date of issue

Prepositions

  • valid for
  • valid until
  • valid in
  • valid under
  • valid through

Etymology

LatinOld FrenchEnglish

The word 'valid' comes from Latin 'validus,' meaning 'strong, powerful, or effective,' which itself comes from the Latin verb 'valere' — 'to be strong.' It entered English through Old French 'valide' in the 16th century, first used in legal contexts to describe documents with full force, then extended to logical arguments in the 17th century.