Consumption is the process of using up resources, such as energy, materials, or time. EXHAUSTION is the state of being completely worn out, which can be caused by over-consumption. Uptake is the process of taking in something, such as nutrients or energy, which is necessary for consumption. EXPENDITURE is the act of spending resources, such as money or energy, in order to consume something. WASTE is the leftover material that is produced from consumption. DEPLETION is the process of using up a resource until it is gone. Intake is the process of taking something in, such as food or water, which is necessary for consumption. USE is the act of utilizing something, such as a tool or resource, for a specific purpose. USAGE is the act of using something, such as a tool or resource, for a specific purpose.