n.
Function: adjective
Date: 12th century
: being or relating to a master: as a : having chief authority : DOMINANT b : SKILLED , PROFICIENT <a prosperous master builder ― Current Biog. > c : PRINCIPAL , PREDOMINANT d : SUPERLATIVE ― often used in combination <a master -liar> e : being a device or mechanism that controls the operation of another mechanism or that establishes a standard (as a dimension or weight) f : being or relating to a master from which duplicates are made