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.
One acre is about 4,046.873 square meters. A square plot of ground 208.7 feet on a side will cover an acre. An American football field, 360 feet by 160 feet, is about 1.3 acres; 12 high school basketball courts are a little more than 1 acre.Here's a way for city dwellers to use a Google map of their neighborhood to get a feel for how big an acre is.t is purely an area of 43,560 square feet. The two sides of a 1-acre rectangular lot can be any lengths as long as multiplying one by the other gives 43,560 (if they are measured in feet). For example, imagine a sidewalk 5 feet wide.