"Well, there's "innumerate/innumeracy", based on "illiterate/illiteracy" (first OED citation, 1959). And then there's that old bugaboo "irregardless" (first citation, 1912)."
I suppose I'm stating the obvious with an observation that forms in "in-" will be resisted because of connotations of "movement into", etc.
"I'd like to offer "inhopefully", in the hope that it escapes from Google into the wild. But how many adjectives ... used "intesticulate" a couple of times in these pages, but those seem like the lot (of course they can't be)."
Apparently "numerate" is fifteenth-century.
I don't know why, but "I can't off-hand think" looks really odd in writing, even though it would be entirely natural in speech. Life, huh?
Andrew Gwilliam
To email me, replace "bottomless pit" with "silverhelm"