In baseball, a strikeout occurs when the batter receives three strikes during his time at bat. Strikeouts are associated with dominance on the part of the pitcher and failure on the part of the batter.
Nolan Ryan has the most career strikeouts in Major League Baseball. During a record 27-year career, he struck out 5,714 batters.
The List
A player is considered "inactive" if he has not played baseball for one year or has announced his retirement.
Stats updated through 2016 season.
References
List of Major League Baseball career strikeout leaders Wikipedia(Text) CC BY-SA