directness has 6 distinct synonyms spread across 2 of its 2 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is indirectness.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
trueness of course toward a goal
“rivaling a hawk in directness of aim”
Synonyms, antonyms and the broader and narrower relations for directness come from Princeton University’s WordNet. Full sources and licences.
the quality of being honest and straightforward in attitude and speech