Leisure is time off, spare time, sweet sweet freedom from the demands of work. It's like playtime for grown-ups.
Leisure is time away from commitments like work or school. Leisure activities might include windsailing, golfing, crocheting a portrait of Betsy Ross, staring at one's navel, whatever. It's the freedom to do what the heck you want. It's not time for punching the clock or writing a paper on the role of matchsticks in the Industrial Revolution; it's kick-your-shoes-off time. If you read a book at your leisure, there's no rush. Leisure is more rare for some than others. "The billionaire was a woman of leisure," but leisure time is a luxury for most.