unassailable
Concise Oxford English Dictionary © 2008 Oxford University Press:
unassailable/ʌnəˈseɪləbl/
▶adjective unable to be attacked, questioned, or defeated.
– derivatives
unassailability noun,
unassailably adverb.
unassailability noun,
unassailably adverb.
'unassailable' also found in these Oxford entries:

