fourth

Adjective

• 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
    

Noun

• the musical interval between one note and another four notes away from it

• one of four equal parts
  • a quarter of a pound
    

• following the third position; number four in a countable series

Adverb

• in the fourth place
  • fourthly, you must pay the rent on the first of the month
    

Related words

• Synonyms: 
  4th , quaternary , one-fourth , one-quarter , quarter , fourth part , twenty-five percent , quartern , fourthly