This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. Impossible to dispute or disprove; undeniable: unassailable truths.

adj. Not subject to attack or seizure; impregnable: an unassailable fortress.

adj. secure against attack; impregnable

adj. undeniable, incontestable or incontrovertible

Not assailable; incapable of being assailed; incontestable; hence, not to be moved or shaken from a purpose.

adj. impossible to assail

adj. without flaws or loopholes

adj. immune to attack; incapable of being tampered with

"Here, in unassailable privacy, they do their tricks for one another, then bask in their own applause."

inviolable    incontestible    incontestable    invulnerable   

invulnerable    inoppugnable   

available    inhalable    salable    saleable    unavailable    unsalable    unsaleable   

impregnable    invulnerable    unscathed    indestructible    foolproof    unbreakable    unimpeachable    impervious    unquestionable    unbeatable