(of a child) not having been adopted (= taken legally into another person's family and taken care of as their own child)

She said the proposal might block grandparents from purchasing health insurance for unadopted grandchildren in their custody. 她说，该提案可能会阻止祖父母为其监护的未被收养的孙子女购买医疗保险。

(of an animal) not having been taken from a place such as a rescue centre to become someone's pet

He helped create Best Friends as an alternative to shelters killing unadopted animals to make space. 他帮助创建了"最好的朋友"这个组织，区别于那些为了腾出空间而对未被收养动物进行安乐死的流浪动物收容所。

(of a road, etc.) private rather than owned and maintained (= kept in good condition) by a local government

Unadopted roads normally have to be maintained by residents, although the local authority may provide street lighting. 通常来说，私家路必须由住户自行维护，尽管地方政府可能会提供街道照明。