cheerful and openhearted; bright and magnanimous
Describes a personality that is upbeat, frank, and generous in spirit. Often used to characterize someone's disposition or attitude.
He has a cheerful and openhearted personality, and can quickly become friends with anyone.
By behaving in a bright and magnanimous way, you can lighten the mood around you.
明朗 means 'bright and clear' and can describe both personality and things like accounting. 明朗闊達 adds the nuance of openheartedness and magnanimity.
闊達 alone means 'openhearted' or 'broad-minded', but is less common as a standalone word. 明朗闊達 combines it with cheerfulness.
A yojijukugo combining 明朗 (bright, cheerful) and 闊達 (openhearted, magnanimous). The exact historical derivation is uncertain, but the compound is conventionally used to describe a cheerful and generous personality.