The Lanham Act is a part of federal law dealing with protection of trademarks.
15 U.S.C. § 1125 – False designations of origin, false descriptions, and dilution forbidden
(a) Civil action
(1) Any person who, on or in connection with any goods or services, or any container for goods, uses in commerce any word, term, name, symbol, or device, or any combination thereof, or any false designation of origin, false or misleading description of fact, or false or misleading representation of fact, which—
(A) is likely to cause confusion, or to cause mistake, or to deceive as to the affiliation, connection, or association of such person with another person, or as to the origin, sponsorship, or approval of his or her goods, services, or commercial activities by another person, or
(B) in commercial advertising or promotion, misrepresents the nature, characteristics, qualities, or geographic origin of his or her or another person’s goods, services, or commercial activities,
shall be liable in a civil action by any person who believes that he or she is or is likely to be damaged by such act.
For example, if I were to start running a website called carrollcountyexaminer dot com. I’d expect to get sued because the examiner dot com has a carroll county site already.