Use 'lark about' to describe light-hearted, playful behavior, often in a social setting.

Playful Context

'Lark about' is casual and may be inappropriate in formal or serious situations.

Not for Formality

Remember it's a British phrase, so it might not be understood or used by English speakers elsewhere.

Suggests procrastination or avoiding responsibilities, often in a subtle or gentle way.

Can indicate someone's frustration with another's lack of focus or seriousness.

Reminds to use the phrase when time is being spent without accomplishing anything.