(a.) Not capable of being defended, unjustifiable; untenable; as, an indefensible position, cause, etc.
Thesaurus Entries
exceptionable, impossible, inadmissible, inexcusable, inexpiable, intolerable, irremissible, objectionable, unacceptable, unallowable, unconscionable, undesirable, unforgivable, unjustifiable, unpardonable, unreasonable, unsuitable, untenable, unwarrantable
