lose has 3 distinct synonyms spread across 3 of its 10 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 5 recorded opposites are keep, win, find, profit, break even.
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.
fail to win
“We lost the battle but we won the war”
1 of the 10 recorded senses carries no synonym, antonym or related term, so it is not shown above. Every sense, with its definition and examples, is on the full entry for lose.
Synonyms, antonyms and the broader and narrower relations for lose come from Princeton University’s WordNet. Full sources and licences.
suffer the loss of a person through death or removal
“She lost her husband in the war”
fail to make money in a business; make a loss or fail to profit
“I lost thousands of dollars on that bad investment!”
withdraw, as from reality
“he lost himslef in his music”