In the context of the Philippines, "poblacion" typically refers to the central or main town of a municipality. It's a term that dates back to the Spanish colonial period when the Spanish established towns and villages (pueblos) throughout the archipelago.
The poblacion was usually the heart of the municipality, containing the church, the town hall, and the market. It was where people from the surrounding rural areas would gather for commerce, religious services, and other activities.
Therefore, the name "poblacion" simply comes from the Spanish word población, reflecting its significance as the main population center within a municipality.