Liveliness or energy — a spirited, animated atmosphere or vigor present in a place or among people.
市場は朝から活気があり、多くの人でにぎわっていた。
The market was lively from the morning and bustling with many people.
新しい店ができて町に活気が戻った。
A new shop opened and the town regained its liveliness.
会議には活気があり、意見が飛び交った。
The meeting was energetic and opinions were exchanged actively.