defensible

1 capable of being defended against physical attack the pioneers retreated to a defensible hillside to take a stand against the raiders Synonyms defendable, tenableRelated Words defended, guarded, protected, safeguarded, secure, secured, shielded; bulletproof, impregnable, indomitable, invincible, inviolable, invulnerable, unassailable, unbeatable, unconquerable, untouchableNear Antonyms vincible, vulnerable; assailable, exposed, imperiled (or imperilled), insecure, liable, open, susceptible, undefended, unguarded, unprotected, unsecured; defenseless, helpless, powerless, weakAntonyms indefensible, untenable

2 capable of being defended with good reasoning against verbal attack there's simply no defensible reason for dropping out of school Synonyms defendable, tenable, justifiable, maintainable, supportable, sustainableRelated Words rational, reasonable, sensible, well-grounded; acceptable, admissible, allowable, exceptionable, legitimate, passable, unobjectionable, viable, warrantable; confirmable, provable, verifiable; explainable, explicableNear Antonyms absurd, illogical, irrational, ridiculous, unsound; extreme, outrageous, unreasonable; groundless, objectionable, unacceptable, unfounded; inexplicable, unexplainableAntonyms indefensible, insupportable, unjustifiable, unsustainable, untenable