“没辙”用于口语，轻松、幽默的用法：我对这调皮的小孩真的没辙了。 “无奈”多用于书面，口语也可以用到，一般用于一些较重要的话题：人生好多无奈。 没辙 是动词，Model：谁（对谁）没辙了。 无奈 既是动词，又是名词，Model：谁很无奈。 谁（什么）有很多的无奈。

没辙，无奈 sometimes have the same meanings. but the uses are different. eg: the car has broken down.we 没辙（here is used as a verb）,means we can't fix it or we can't do anything about it. the car has broken down.we are 无奈（here is used as a adj.）implies much the same meaning ,we feel helpless,we can not find a way to solve this problem. 无奈can also used as a adv. eg：我们无奈地走路回家。means we have to walk home reluctantly, because we can not do anything about the broken car. HOPE THIS CAN HELP.

没辙：can find no way out; it is a dialect from Beijing.没辙=无奈。 无奈： 动词（verb）你出的问题没有主题，我很无奈 名词（noun）人生都有许许多多的无奈 连词（ conjunction）我本想星期天去郊游，无奈天不作美下起雨来，只好作罢了。

问你女朋友啊 哈哈

没辙 means 没办法 have no way to do something 无奈：have no choice normally, they are the same. but 无奈 highlights the feeling, and 没辙 highlights the objective conditions.