prosecute (v.)

early 15c., prosecuten, "to follow up, pursue with a view to carry out or obtain" (some course or action), from Latin prosecutus, past participle of prosequi "follow after, accompany; chase, pursue; attack, assail, abuse," from pro- "forward" (see pro-) + sequi "follow" (from PIE root *sekw- (1) "to follow"). Meaning "bring to a court of law, seek to obtain by legal process" is recorded from 1570s. The Latin verb in Old French became prosequer, vulgarly porsuir, which passed to English as pursue.