GIS Dictionary

quadrangle

A rectangular map bounded by lines of latitude and longitude, often a map sheet in either the 7.5-minute or ...

quadrant

1 In a rectangular coordinate system, any of the quarters formed by the central intersection of x and ...

quadrat

In spatial sampling, one of a set of identically-sized areas, often rectangular, within which the ...

quadtree

A method for encoding raster data that reduces storage requirements and improves access speeds by storing values only for homogeneous ...

quantile

In a data distribution, a value representing a class break, where classes contain approximately equal numbers of observations. The ...

query

A request to select features or records from a database. A query is often written as a statement or ...