A collection of baseball games, generally played in October, often viewed by aficionados in a light similar to religious ritual. Term first coined in the 1950s by the inimitable Walt Kelly, cartoonist, humorist, and linguist extraordinaire. (We have met the enemy and he is us.) Example: 2001 was the first year the World Serious lasted into November.
WORLD SERIOUS
Meaning of WORLD SERIOUS in English
Slang English vocab. Английский сленговый словарь. 2012