What does Boat Rudder mean?

Boat Rudder meaning in Urban Dictionary

minimal, abrasive singing technique which a basic of metalcore and associated music genres; distinct through the vocal varieties of thrash steel, black steel and demise metal. The term is primarily used by metalcore's detractors and originates from a well known lyrical interpretation of Trivium's 'Pull Harder regarding Strings of one's Martyr' on Youtube.