an idea which we get by attending to the fleeting and perpetually perishing part of succession; the idea of succession being acquired by reflecting on that train of ideas which constantly follow one another in our minds, as long as we are awake. The simple modes of duration are any different lengths of it whereof we have distinct ideas, as hours, days, years, time, eternity, &c.

as marked by certain periods and measures, is what we most properly call time. See Time.