Definition of blister. 1  1 : a fluid-filled elevation of the epidermis â compare water blister. 2  2 : an enclosed raised spot (as in paint) resembling a blister. 3  3 : an agent (such as lewisite) that causes blistering. 4  4 : a fungal disease of plants marked by raised patches on the leaves.
One acre equals 0.0015625 square miles, 4,840 square yards, 43,560 square feet or about 4,047 square metres (0.405 hectares) (see below). While all modern variants of the acre contain 4,840 square yards, there are alternative definitions of a yard, so the exact size of an acre depends on which yard it is based.
Alternatively, you may use the converters below to convert any other values. 1 Acre = 43 560 Square Feet. Acre is an imperial and US customary system area unit. In metric system, it's replaced by hectare. The abbreviation is ac. Square foot is an imperial and US customary area unit. In metric system, it's replaced by square meters (metres). The abbreviations are sq ft and ft 2 .