Lazy, indolent, slothful, faineant are comparable primarily as applied to persons, their powers, movements, and actions, but also in some degree to things.
All mean not easily aroused to action or activity. Lazy especially when applied to persons suggests a disinclination or aversion to effort or work and usually connotes idleness or dawdling, even when one is supposedly at work; the term is commonly derogatory.
Indolent implies an habitual love of ease and a settled dislike of movement or activity.
Slothful suggests the temper or indolence of one who is inactive when he knows he should be active or who moves or acts with excessive slowness when speed is essential.
Faineant implies both a slothful temper and a disposition to remain idly indifferent in spite of pressure or urgency.