crookedness has 5 distinct synonyms spread across 2 of its 3 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 straightness.
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.
a tortuous and twisted shape or position
“they built a tree house in the tortuosities of its boughs”
having or distinguished by crooks or curves or bends or angles
Synonyms, antonyms and the broader and narrower relations for crookedness come from Princeton University’s WordNet. Full sources and licences.