Definitions
1.adjectiveBased on hypothesis rather than experiment."In his opening argument, the student mentioned nothing beyond his a priori knowledge."
2.adjectiveSelf-evident, intuitively obvious.
3.adjectivePresumed without analysis.
4.adjective(conlanging) Developed entirely from scratch, without deriving it from existing languages.
5.adverbIn a way based on theoretical deduction rather than empirical observation.