color主要有三层含义：

1.诉讼用语。当事人一方承认另一方有表面上的诉权〔prima facie right of action〕，但同时又提出新的事实证明另一方的主张不能构成诉讼理由〔cause of action; ground of action〕即对方的诉讼理由是不充分的。有这样一条规则：在既承认而又持异议的答辩中，必须通过明示或默示，先承认或「给予」表面权利〔confession and avoidance should give colour〕，而后再予以否定。

2.肤色；有色人种的肤色

3.生动；多彩

在这两个词组中，color的意思均与第一种“表面”有关。

color of law法律权力之表象；表面合法的权力

指无其实的法律权力之外观。该词常指因违法者披有国家权力之外衣而使权力滥用成为可能。一国家官员的行为，不论该行为是否在其职权范围内，只要此官员声称其正在履行公务即为依表面合法权力而为的行为〔act under color of law〕。在美国，依《1871年民权法》〔Civil Rights Act of 1871〕的规定，color of law与州行为〔state action〕同义，指官员与某一州有密切关联以致其所作出的行为被视为如同该州的行为。 Color of law refers to an appearance of legal power to act that may operate in violation of law. For example, if a police officer acts with the "color of law" authority to arrest someone, the arrest, if it is made without probable cause, may actually be in violation of law.

Color of title 表面上的所有权

用于收回不动产的诉讼之中，指由于所有权转让过程中的瑕疵导致所有权转让无效，从而产生了形式上而非事实上或法律承认的所有权。 an apparent but invalid title based upon a written instrument or record also : the instrument itself. 2 : an apparent ownership claimed by adverse possession.

以下为相关双语示例，供参考：

Under the Compact of Free Association, RMI citizens are allowed to freely enter, reside, and work in the U.S. and its territories, and authorized to participate in certain federal programs, including eligibility in Medicaid as aliens permanently residing under color of law in the United States and its territories. 

根据《自由联盟条约》，允许马绍尔公民自由进入美国及其领土，并在那里居住和工作，并准予马绍尔公民参加某些联邦方案，包括根据法律权力之表象永久居住在美国及其领土的外国人享受的 Medicaid 资格。