i-adjective
unthinkable; outrageous; absurd
Archaic form of とんでもない. Used in older texts or stylized speech to express strong denial or that something is beyond consideration.
See also: とんでもない
「とでもないことを申すな」と老人は言った。
"Don't say such outrageous things," the old man said.
昔の小説には「とでもない話
In old novels, the expression "it's an unthinkable story" often appears.