fourth

fourth (http://definr.com/fourth)

     adj : coming next after the third and just before the fifth in
           position or time or degree or magnitude; "the
           quaternary period of geologic time extends from the end
           of the tertiary period to the present" [syn: 4th, quaternary]
     n 1: following the third position; number four in a countable
          series
     2: one of four equal parts; "a quarter of a pound" [syn: one-fourth,
         quarter, fourth part, twenty-five percent, quartern]
     3: the musical interval between one note and another four notes
        away from it
     adv : in the fourth place; "fourthly, you must pay the rent on the
           first of the month" [syn: fourthly]