Peoria is a city in Maricopa and Yavapai counties in the state of Arizona. Most of the city is located in Maricopa County while a tiny portion in the north is in Yavapai County. It is a major suburb of Phoenix. According to 2019 Census Bureau estimates, the population of the city is 175,961. Peoria is currently the sixth-largest city in Arizona in land area and the ninth-largest in population. It was named after Peoria, Illinois. The word peoria is a corruption of the Miami-Illinois word for 'prairie fire'. It is the spring training home of the San Diego Padres and Seattle Mariners, who share the Peoria Sports Complex.