lour(verb) verb1. set lowerSimilar word(s): lowerDefinition categories: change, devalue2. make lower or quieterSimilar word(s): lowerDefinition categories: change, decrease, lessen, minify3. look angry or sullen, wrinkle one's forehead, as if to signal disapprovalSimilar word(s): frown, glower, lowerDefinition categories: body, grimace