The opposite of an acid is a base, and that's exactly what an antacid is. Antacids make you feel better by increasing the pH balance in your stomach. The pH system is a scale for measuring the acidity or alkalinity of a given environment (in this case, your stomach). The scale goes from 0 to 14. A pH of 7 is neutral. Below 7 is acid. Above 7 is alkaline.
Economy is the large set of inter-related economic production and consumption activities which aid in determining how scarce resources are allocated.
A given economy is the end result of a process that involves its technological evolution, history and social organization, as well as its geography, natural resource endowment, and ecology, among other factors. These factors give context, content, and set the conditions and parameters in which an economy functions.