impugnable

Open to attack

Impugnable describes something that can be challenged, disputed, or called into question.

The word applies to claims, motives, or evidence vulnerable to attack: His credentials were impugnable.

It's the opposite of impregnable, though the two are sometimes confused.

The more common form is the verb impugn.

challengeable

contestable

Able to be challenged

disputableAble to be challenged
questionableOf uncertain validity
debatableOpen to question

arguable · refutable · controvertible · deniable · opposable · attackable · assailable · rebuttable · objectionable · exceptionable

vulnerable

exposed

Out in open

assailableOpen to attack
susceptibleEasily influenced or harmed
defenselessWithout means to resist

unprotected · penetrable · open · unguarded · unshielded · pregnable · attackable · accessible · insecure · endangered

indefensible

untenable

Impossible to maintain

unsoundWeak or flawed
baselessLacking factual support
groundlessLacking factual support

unjustifiable · unwarranted · unsupportable · unsubstantiated · fallacious · specious · invalid · illogical · unfounded · weak

discreditable

dishonored

Brought shame upon

disgracedBrought into shame
malignedFalsely disparaged
disparagedCriticized with contempt

denigrated · undermined · discredited · invalidated · repudiated · debunked · disproved

Opposites

vulnerability to challenge

impugnableunimpeachable

Beyond criticism or doubt

unassailable · incontrovertible · irrefutable · unquestionable · indisputable

Family

repugnant, impugn, pugnacious, pugilist, impugning, impugned, pugilism, impugner

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