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No Title Sort descending Definition
1 Absolute Orientation

Scaling,leveling and orientation to ground control of a stereo pair of aerial photographs during the photogrammetric setup process.

2 Accuracy

closeness of agreement between a test result and the accepted reference value

3 Acetate Overlays

A nonflammable plastic sheeting used as a base for photographic fils or as a drafting base for overlays where critical registration is not required.

4 Address

[cadastral and land records] A designation of the location of a person's residence or workplace, an organization, or a building, consisting of numerical and text elements such as a street number, street name, and city arranged in a particular format.


5 Address Matching

The ability to match an address component to its geographic location on the ground 

6 Aerial photograph

Photograph taken from an aerial platform (usually an aeroplane), either vertically or obliquely.

7 Affine Transformation

Coordinate transformation to convert map coordinates into database coordinates

8 Aggregation

The process of combining smaller spatial units, and the data they contain, into larger spatial units by dissolving common boundaries and lumping the data together.

9 Altitude

Altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context.

10 Annotation

Text on a drawing or map associated with graphic entities.

11 Application

A program (software) or web mapping service designed to perform a specific task. Examples include word processing software, database programs, and mapping tools.

GIS applications can be used to solve problems, automate tasks, and generate information within a specific field of interest. They can also be used to search, analyze, and map data to answer particular questions.

12 Application Services

OWS Services operating on user devices or servers that have network connectivity. Users use Application Services to access Registry, Portrayal, Processing and Data Services. Application Services commonly, but not necessarily, provide user-oriented displays of geospatial content and support user interaction at the user terminal.

13 Arc

An ordered string of vertices (x, y coordinate pairs) that begin at one location and end at another. Connecting the arc’s vertices creates a line. The vertices at each endpoint of an arc called nodes.

14 ArcCatalog

[software] ArcCatalog is an application in the ArcGIS suite used to manage geographic data – similar to windows file explorer.

15 ArcGIS Server Web service

[ESRI software] A Web service processed and executed from within an ArcGIS server. Each Web service has a distinct HTTP location (URL). Web access is enabled by default for all ArcGIS Server services, but can be turned off by an administrator.

16 ArcGlobe

[software] ArcGlobe is a global three-dimensional visualization and analysis environment as part of the Esri ArcGIS suite (3D analyst), specializing in global datasets and larger study areas.

17 Architecture

An abstract technical description of a system or collection of systems. Modern software architectures employ interoperability interfaces to enable enterprises and whole industries to establish coherent, flexible, integrated information flows that can be implemented with heterogeneous but intercommunicating software systems. The OpenGIS Specification defines the interoperability interfaces that make it possible to include geographic information in these information flows. Conceptually based, architecture does not contain the level of detail needed for construction

18 Area of Interest

A user defined area (represented by a bounding box, circle or polygon). Often used as a filter in a query.

19 Aspect

[GIS processing] Aspect is the slope direction on a terrain surface. Aspect is measured clockwise starting North as 0° to 360° North again with flat areas given a value of -1 (or 0 degrees).

20 Attribute

named property of an entity

21 Attribute Data

Descriptive information about features or elements of a database. For a database feature like census tract, attributes might include many demographic facts including total population, average income, and age. In statistical parlance, an attribute is a `variable,` whereas the database feature represents an `observation` of the variable.

22 Attribute table

[data structure] An attribute table stores non-spatial information in columns and rows about geographic data – similar to spreadsheets.

23 Automated Conversion

The process of converting maps and drawings into a digital format while reducing or eliminating operator intervention. Scanning is one form of automated conversion. Heads-up digitizing via tracing a raster image displayed on a computer screen is another form.

24 Automated Mapping

The use of computer graphics technology to produce maps. May include specialized CAD technology for digitizing and editing map features, and DBMS technology to produce thematic maps.

25 Axis

A reference line in a coordinate system

26 Azimuth resolution

resolution in the cross-range direction

27 Azimuthal projections

Map projections in which the surface of the globe is projected onto a flat plane.