Not defended or not able to be defended.(adjective)
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Use "assailable" in a sentence
"Scientific reasoning is assailable, that is what peer review is for and is exactly how and why the amazing errors in the IPCC report were found out and shot down."
"The U.S. has the most sophisticated military hardware in the world and is able to project air support from aircraft carriers and bases in Japan, neither of which are easily assailable."
"First of all, the otherwise-unassailable movie (Orson Welles, Leonard Nimoy, Judd Nelson and Robert Stack — what could possibly go wrong?) introduced a thoroughly assailable character in Wheelie, a pre-pubescent robot man-child who talks in rhymes and turns into a bubbly alien car."