[mass noun]the improvement of something 改善,改进,提高 they believed that what they were doing was vital for the betterment of society. 他们相信他们正在做的事情对社会改良至关重要。 ■the enhanced value of real property arising from local improvements (因当地环境改善而产生的)(不动产)增值 [as modifier]a betterment charge. 不动产增值税。