Those rare but precious moments when the world becomes a wonderful place to live are called 'peak experiences'.
A peak experience is, therefore, a temporary situation where our consciousness is experiencing a more functional way of being.
If this is too abstract, think of a day in your life where everything just went smoothly. Where you woke up in a good mood. Breakfast was easy, work just went well and you came home happy. This is called a peak experience. If this would persist it would be a peak state. The description here matches the "flow"-state, where everything is just working out and life feels in flow to you.