負心 means to betray, be ungrateful, go against one's conscience etc. adding 人, it means someone who betrays, usually a man in love matters. replacing it with 汉 is a definite colloquial term for a male heartless philanderer. with a 者, it means a person who betrays and this depends on the context.

是指玩弄别人的爱情，抛弃痴心女子，对感情不专一的男子（heart breaker） eg陈世美忘恩负义，抛弃妻子，是一个典型的负心汉，受到了人们的指责。

负心汉一般指的是玩弄别人的爱情，抛弃痴心女子，对感情不专一的男人。英文翻译 ：heart breaker （From Baidu） 【http://baike.baidu.com/link?url=dWNMoN3Kjw3CCyd48gHOwnC_gryDxoZqw6oLW5F1BXR9IgSzPO4wDpALWh--kamGJzGRJ_m9kHXWs91j6GzU5q】 例句：The dirty bum is going to pay. 这负心汉会付出代价的。 【http://danci.911cha.com/%E8%B4%9F%E5%BF%83%E6%B1%89.html】

If a girl is serious and sincere about a relationship with a guy,but the guy is just see it as a game and cheated her,then the guy is 负心汉。 Or you two used to be a couple,however,as the man get higher position or for a better work,he deserted the girlfriend or wife, he denied all the relationship with her,then he is called a 负心汉。 All in all,he is a bad guy.

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