Incontrovertible, a.
Not controvertible; too clear or certain to admit of dispute; indisputable. Sir T. Browne. -- In*con`tro*ver"ti*ble*ness, n. -- In*con`tro*ver"ti*bly, adv.
Shades of meaning
Fernald lists incontrovertible only as an antonym, under absurd.
He lists it without comment; the entries above explain its neighbors.
Synonyms
none given