Capital city definition from wikipedia
: A capital city or capital town (or simply capital) is the municipality enjoying primary status in a state, country, province, or other region, usually as its seat of government.
A cap is a form of headgear. Caps have crowns that fit very close to the head and have no brim or only a visor. They are typically designed for warmth and, when including a visor, blocking sunlight from the eyes. They come in many shapes and sizes.