Based on the clue 'a division of geologic time', what is the answer?

Based on the clue 'a dividing partition between 2 cavities like the o...', what is the answer? Based on the clue 'a division into 2 usually contradictory parts or o...', what is the answer? What is associated with: a division of a group into mutually antagonistic factions like the catholic church in 1054? Based on the clue 'a division of a play or the plays setting', what is the answer? Based on the clue 'a dizzy sensation of tilting within stable surroun...', what is the answer? Based on the clue 'a dj on wkrp hes now head of the class', what is the answer? What is associated with: a docked horses tail or a short haircut for women popular in the 1920s? Based on the clue 'a doctor could tell you that qid which is the abbr...', what is the answer?