The word "pedantic" originates from the term 'pedant,' which initially referred to a schoolmaster or tutor.  The word's etymology traces back to the Italian "pedante" and French "pédant," both signifying a teacher.  In Shakespeare's day, a pedant was a male schoolteacher, but over time, "pedant" and consequently "pedantic" evolved to describe someone excessively focused on minor details or rules, often in a pompous or showy way. 

Examples of using pedantic in a sentence:  
"For years, pedantic scholars have crowed about the debt rock owes the blues." 
"The administrators must simplify the process and tell referees to be less pedantic." 
"We thought he was a bit pedantic at times."
"The negotiations are now down to detail that might seem pedantic elsewhere." 
"Yet such is the established way of things that it seems almost pedantic to be pointing this out." 
"Again, it seems pedantic to quibble about the differences between strikers and attacking midfielders." 
"This may seem a pedantic distinction, but it is an extremely important one." 

Just the facts:

PEDANTIC Definition & Meaning - Merriam-Webster