Certificate of Citizenship
Identity document proving U.S. citizenship. Certificates of citizenship are issued to derivative citizens and to persons who acquired U.S. citizenship (See definitions for Acquired and Derivative Citizenship).
Source: U.S. Citizenship and Immigration Services
A document issued by the Department of Homeland Security as proof that the person is a U.S. citizen by birth (when born abroad) or derivation (not from naturalization). The Child Citizenship Act of 2001 gives American citizenship automatically to certain foreign-born children of American citizens. These children can apply for certificates of citizenship.
Source: U.S. Department of State.