Refers to a state of deep, lasting happiness or well-being, often used in formal or philosophical contexts. Can also be used as an adjective with な.
The happiness of my family is the most important thing.
He lived a happy life.
She feels true happiness right now.
The couple lives happily in a quiet village.
He lived a happy life.
Small acts of kindness bring happiness to people.
right to the pursuit of happiness
gross national happiness; GNH