Leisure: Time of one's own, in which one can do as one pleases.
The concept of leisure is often opposed to that of work, which accordingly may be defined as time not of one's own, in which one does as others please, in order to obtain money, food, or status.
Leisure seems to be quite important in two senses: First, it is the proper motive for work: to acquire enough to also have some time in which one can do as one pleases; and second, it is one of the foundations of civilization and science, since many of the products of these have been invented or discovered in leisure-time.
The reason for the first point is especially that what human beings like most tends to be to do as they please when they please; the reason for the second point is that human creativity seems to depend much on freedom of strain and stress.
There is, especially in Western society, possibly because of the calvinist work ethic, a rather unhealthy tendency to insist that man - and according to modern academic feminists, woman also and especially - lives to work, rather than that man works to live, in leisure.
And in any case, a society where few have leisure, or such leisure as they have must be mostly spent on recuperating from work, seems to be in effect to those many to be much like slavery, even if they are nominally free wage-earners.
"The end of labor is to obtain leisure." (Aristotle)