English to English

noun (n)

• someone who systematically obstructs some action that others want to take

  seseorang yang sistematis obstructs beberapa tindakan yang lain ingin mengambil

  Synonym:
  obstructer, obstructionist, obstructor, thwarter
  

  source: wordnet30
• someone who offers opposition

  seseorang yang menawarkan oposisi

  Synonym:
  adversary, antagonist, opponent, opposer
  Antonym:
  agonist
  

  source: wordnet30
• One who resists.

  yang menolak.

  source: webster1913