What is the meaning of theology?

noun

• The rational and systematic study of religion and its influences and of the nature of religious truth.
  • synonyms: divinity
• A particular system or school of religious beliefs and teachings.
  • usage: "Jewish theology"; "Roman Catholic theology"
  • synonyms: theological system
• The learned profession acquired by specialized courses in religion (usually taught at a college or seminary. )
  • usage: "he studied theology at Oxford"