勒 On the HSK 7-9 vocabulary list, at CEFR level C2. lè ㄌㄜˋ bridle halter headstall literary to rein in to compel to force to carve to engrave literary to command to lead (an army etc) literary lux (abbr. for 勒克斯[le4 ke4 si1]) physics lēi ㄌㄟ to strap tightly to bind Sources CC-CEDICT, CC BY-SA 4.0 pinyinjs, Apache-2.0 国际中文教育中文水平等级标准, 中华人民共和国教育部, MIT