question has 16 distinct synonyms spread across 10 of its 11 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 answer.
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.
an instance of questioning
“there was a question about my training”
uncertainty about the truth or factuality or existence of something
“the dubiousness of his claim”
an informal reference to a marriage proposal
“he was ready to pop the question”
challenge the accuracy, probity, or propriety of
“We must question your judgment in this matter”
Synonyms, antonyms and the broader and narrower relations for question come from Princeton University’s WordNet. Full sources and licences.