De`mar*ca"tion (?), n. [F. démarcation; pref. dé- (L. de) + marquer to mark, of German origin. See Mark.] The act of marking, or of ascertaining and setting a limit; separation; distinction.

The speculative line of demarcation, where obedience ought to end and resistance must begin, is faint, obscure, and not easily definable.