Question: Most strikeouts by mlb pitcher in a season?
Disambiguated questions and answers: question: Most strikeouts by official mlb pitcher in a season?
Most strikeouts by mlb pitcher in a season, including time in independent American Association league?
answer: 417 strikeouts
417
513 strikeouts
513
Natural Questions answer: Mark Reynolds (from the Wikipedia article "List of Major League Baseball record holders")