bloodless has 6 distinct synonyms spread across 2 of its 5 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 bloody.
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.
destitute of blood or apparently so
“the bloodless carcass of my Hector sold”
free from blood or bloodshed
“bloodless surgery”
2 of the 5 recorded senses carry no synonym, antonym or related term, so they are not shown above. Every sense, with its definition and examples, is on the full entry for bloodless.
Synonyms, antonyms and the broader and narrower relations for bloodless come from Princeton University’s WordNet. Full sources and licences.