Thesaurus.com
Dictionary.com
Definitions

unassailable

[uhn-uh-sey-luh-buhl] / ˌʌn əˈseɪ lə bəl /
ADJECTIVE
certain
Synonyms
STRONGEST
absolute conclusive indisputable infallible irrefutable undeniable unequivocal
WEAK
ascertained authoritative clear confirmable definite demonstrable destined determined establishable evident firm fixed genuine guaranteed hard having down pat in the bag inarguable incontestable incontrovertible indubitable known on ice plain positive predestined provable real reliable safe salted away set sound supreme sure sure thing true trustworthy unambiguous undisputable undoubted unerring unmistakable unquestionable verifiable
Antonyms
STRONGEST
disputable doubtful dubious imperfect indefinite questionable refutable uncertain unsure vague

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

For the next decade, he was unassailable, with hits such as Stronger, Gold Digger and Heartless pushing the boundaries of rap.

From BBC • Apr. 7, 2026

Ultimately, the desire for a new jazz age is a wish for a new national identity as glamorous and unassailable as old Hollywood.

From Los Angeles Times • Jan. 28, 2026

Mr. Maduro’s prosecution is therefore legally unassailable not because it breaks new ground, but because it so closely follows a 36-year-old template the federal courts have already validated.

From The Wall Street Journal • Jan. 4, 2026

The home side have taken an unassailable 3-0 lead in only 11 days of cricket.

From BBC • Dec. 23, 2025

Yet the Rad Lab’s standing with the AEC was not unassailable.

From "Big Science" by Michael Hiltzik