adj
Uncommon
invalid
ihn-VAL-ihd
Invalid (adj) means not legally or officially acceptable; not valid. Example: “Your passport is invalid because it expired last year.”
adj
1
Not legally or officially acceptable; not valid.
"Your passport is invalid because it expired last year."
"The referee ruled the goal invalid due to an offside."
noun
1
A person who is chronically ill, disabled, or too weak to care for themselves.
"He spent his final years as an invalid, cared for by his daughter."
"After the long illness, the old man lived quietly as an invalid at home."
"In the novel, the heroine looks after her aunt, a frail invalid who rarely leaves bed."
How to use invalid
Learner’s notesIn plain EnglishEither "not valid/acceptable" (adjective) or an old-fashioned word for a sick or disabled person (noun).
Common mistake
Note the stress shift: "IN-valid" (noun, a sick person) vs "in-VAL-id" (adjective, not valid).
When to use it
The noun sense ("an invalid") is now considered old-fashioned and can sound insensitive; more neutral terms are preferred today.
Common pairings
invalid argument
invalid password
declared invalid
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Word forms
- Plural
- invalids
- Third person singular
- invalids
- Past tense
- invalided
- Comparative
- more invalid
- Superlative
- most invalid
Fill the gap
Can you complete this real example?
Your passport is _____ because it expired last year.
Etymology
From in- ("not") + valid, from Latin validus ("strong").
Synonyms
View more →Antonyms
Related words
Rhymes for invalid
See all rhymes for invalid →Frequently asked questions
What does “invalid” mean?
The word “invalid” means not legally or officially acceptable; not valid. In plain terms, either "not valid/acceptable" (adjective) or an old-fashioned word for a sick or disabled person (noun).
How do you pronounce “invalid”?
“Invalid” is pronounced ihn-VAL-ihd (/ɪnˈvæl.ɪd/ in IPA).
How do you use “invalid” in a sentence?
Here is “invalid” used in a sentence: “Your passport is invalid because it expired last year.”
What part of speech is “invalid”?
Depending on how it is used, “invalid” can be an adjective and a noun.
Where does the word “invalid” come from?
The word “invalid” comes from Latin. From in- ("not") + valid, from Latin validus ("strong").
Is “invalid” a common word?
“Invalid” is an uncommon word in modern English.
How many meanings does “invalid” have?
“Invalid” has 2 distinct senses listed in this dictionary. The most common is: not legally or officially acceptable; not valid.
What is the difference between "invalid" (in-VAL-id) and "invalid" (IN-va-lid)?
These are two different words that share a spelling but not a pronunciation or meaning. Stressed on the second syllable, invalid means not legally or officially acceptable, such as an invalid passport; stressed on the first syllable, invalid is an older term for a person who is chronically ill or too weak to care for themselves.
What is the difference between "invalid" and "null and void"?
Invalid describes something that fails to meet the requirements needed to be legally or officially accepted, such as an invalid contract or ID. "Null and void" is a legal phrase meaning something has no legal force at all, which is a stronger and more formal way of expressing a similar idea.
Why is the noun sense of "invalid" considered outdated?
The noun "invalid," meaning a chronically ill or disabled person, is now widely seen as outdated and potentially disrespectful, since it defines a person by illness rather than treating them as an individual. Modern usage favors more specific and respectful terms instead.
