Is Boston a big city or small city?

I'm curious to know, is Boston considered a big city or a small city? It's well-known for its rich history, world-class universities, and bustling downtown area, but how does it stack up against other major metropolitan areas? Is it a major hub for commerce, culture, and entertainment, or does it retain a more intimate, small-town charm? I'm eager to hear your thoughts on this question, as it could help me better understand the city's place in the broader context of American urban life.