legally

ad. 合法地
n. 合法地,在法律上

You are not legally bound to answer these questions.

在法律上，你没有义务非回答这些问题不可。

A name, symbol, or other device identifying a product, officially registered and legally restricted to the use of the owner or manufacturer.

商标，牌号标明产品的名字、符号或其它设计，经过正式注册，并只合法地限于其拥有者或制造商使用