Wiktionary
unassailably
adv. In an unassailable manner.
WordNet
unassailably
adv. in an unalterable and unchangeable manner; "his views were unchangeably fixed" [syn: unalterably, unchangeably, immutably]
Usage examples of "unassailably".
He then explained that Freud experts tended to be cagey because they are polarised between those who think Freud is unassailably great and those who think he took way too much drugs for his own good.