[mass noun]the action or state of forcing or being forced to do something; constraint (被)强迫,(被)强制 the payment was made under compulsion. 支付是被强制执行的。
an irresistible urge to behave in a certain way, especially against one's conscious wishes (尤指违反本人意愿的)不可抗拒的冲动;强迫性冲动;强迫作用 he felt a compulsion to babble on about what had happened. 他感到一种无法抗拒的冲动迫使他把所发生的事情糊里糊涂地说出来。
语源
late Middle English: via Old French from late Latin compulsio(n-), from compellere 'to drive, force' (see compel)