unable
6 synonyms and 1 antonyms for unable, grouped by meaning and by how common each one is.
Adj — Not having the ability, power, or means to do something.
Synonyms
Less common
Still standard English, but they carry more weight.
Rare, literary or technical
Precise, but they will stand out — check the sense before using one.
Antonyms
How to use unable
The word patterns that sound natural to a native speaker.
Etymology
From Middle English unable, formed from un- ("not") plus able.
Full origin of unable →Frequently asked questions
What does “unable” mean?
The word “unable” means not having the ability, power, or means to do something. In plain terms, lacking the power, skill, or opportunity to do something.
How do you pronounce “unable”?
“Unable” is pronounced uhn-AYBL (/ʌnˈeɪbl̩/ in IPA).
How do you use “unable” in a sentence?
Here is “unable” used in a sentence: “He was unable to attend the meeting because of a flight delay.”
What is the opposite of “unable”?
The opposite of “unable” — its antonyms — is able.
What part of speech is “unable”?
“Unable” is an adjective.
Where does the word “unable” come from?
The word “unable” comes from Middle English. From Middle English unable, formed from un- ("not") plus able.
Is “unable” a common word?
“Unable” is a fairly common word in modern English, usually learned at around the B1 level.
What is the difference between unable and disable?
Unable is an adjective describing a lack of ability — "I was unable to attend." Disable is a verb meaning to switch something off or take away a capability, as in "disable the alarm." The confusion comes from their shared root, but unable describes a state, while disable describes an action that causes one.
What is the opposite of unable?
The direct opposite is "able," meaning you have the ability, power, or means to do something. Other positives include capable and competent. Where unable signals a limit or barrier, able signals that the path is open. Simply removing the "un-" prefix flips the meaning entirely.
What is the difference between unable and incapable?
The two overlap, but unable often points to a specific situation — "unable to make it today" — while incapable suggests a broader, more lasting lack of ability, as in "incapable of lying." Being unable to do one thing does not make you incapable in general; incapable is the stronger, more sweeping word.