Prior definition: preceding in time or in order; earlier or former; previous.. See examples of PRIOR used in a sentence. Definition of prior adjective in Oxford Advanced Learner's Dictionary. Meaning , pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. Definition Previous and prior are two words that are often used interchangeably, but they actually have slightly different meanings . Previous refers to something that came before in time or order, while prior refers to something that is earlier in time or rank. In other words, previous is more commonly used to refer to something that happened immediately before, while prior can refer to something that happened at any point in the past. Usage When it comes to usage, previous is more commonly ... The meaning of PRIOR is earlier in time or order. How to use prior in a sentence. Synonym Discussion of Prior .