What does 'moonlighting' refer to in a professional context?

In a professional context, 'moonlighting' specifically refers to the practice of working a second job outside of regular working hours. This typically means that an individual maintains their primary job while simultaneously engaging in additional employment during evenings, weekends, or other off-hours. This could involve various types of work, such as freelance projects, part-time positions, or consulting jobs, and it can serve as a means for additional income or professional experience.

The other options presented do not align with the definition of moonlighting. Taking leave from work to pursue education indicates a temporary absence from one’s primary job for learning purposes. Volunteering within the community refers to unpaid work aimed at benefitting others, rather than a secondary paid job. Participating in a work-related training program involves enhancing skills or knowledge within the context of one's current position, rather than engaging in a separate job. Thus, the clear distinction of working a second job outside of conventional hours establishes why the correct answer is the one that identifies moonlighting accurately.