What's the difference between i.e. and e.g.?
late 14c., "persecution," also "action of pursuit," from Anglo-French purseute, from Old French porsuite "a search, pursuit" (14c., Modern French poursuite), from porsivre (see pursue). Sense of "one's profession, recreation, etc." first recorded 1520s. As a type of track cycling race from 1938.