noun, na-adjective
cheerful and openhearted
Describes a personality that is bright, frank, and free from gloom or hidden feelings. Often used to characterize someone's disposition or atmosphere.
彼は明朗快活な性格で、誰とでもすぐに仲良くなれる。
He has a cheerful and openhearted personality, and can quickly become friends with anyone.
明朗快活に振る舞うことで、周りの雰囲気も明るくなる。
By behaving in a cheerful and openhearted manner, you can brighten the atmosphere around you.
A yojijukugo combining 明朗 (bright, clear) and 快活 (cheerful, lively). The exact historical derivation is uncertain, but the compound is conventionally associated with a cheerful and openhearted disposition.