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Eccentricity

A measure of how much an ellipse deviates from a circle, expressed as the ratio of the distance between the center and one focus of an ellipsoid to the length of its semimajor axis. The square of the eccentricity, e2, is commonly used with the semimajor axis a to define a spheroid in map projection equations.
(Source: ArcGIS dictionary)

Edge Matching

Operation performed to join disconnected vector or polygon data together ensuring one continuous feature(s).

Ellipsoid

When used to represent the earth, an oblate ellipsoid of revolution, made by rotating an ellipse about its minor axis.
(Source: ArcGIS dictionary)

Enhanced Point of Interest (EPOI)

The Enhanced Points of Interest (EPOI) V1.4 file is a national database of nearly 1 million Canadian business and recreational points of interest. Engineered using CanMap® Streetfiles, each EPOI has been accurately geocoded and precisely placed; two criteria that are fundamental to any successful location sensitive service.

This location enriched point of interest database allows users to see and analyse selected point of interest data in a given geographic area, enabling applications such as wireless location-based services (LBS), Web, Telematics, planning, real estate multiple listing services (MLS), retail site analysis, competitive and market research, intelligent routing, sales territory analysis, business and tourism.

Enhanced Postal Code File

The Enhanced Postal Code File V6.3 is a point database representation of postal codes across Canada, with a geographic link to Statistic Canada's standard 1996 Census Boundaries.

As in the Six Digit Postal Code file, the Enhanced Postal Code File provides superior geographic positioning based on CanMap, enabling users to accurately geocode and map the location and distribution of their data for spatial analysis.

As in the Six Digit Postal Code file, the Enhanced Postal Code File provides superior geographic positioning based on CanMap, enabling users to accurately geocode and map the location and distribution of their data for spatial analysis

Enumeration Area (EA)

Refers to the geographic area canvassed by one census representative. It is the smallest geographic area for which census data is reported. An Enumeration Area may contain approximately 125 to 440 dwellings depending on whether it is located in a rural or urban area respectively.

Equal Area Projection

A projection in which the whole of the map as well as each part has the same proportional area as the corresponding part of the earth. An equal area projection may distort shape, angle, scale, or any combination thereof. No flat map can be both equal area and conformal.
(Source: ArcGIS dictionary)

Equator

The parallel of reference that is equidistant from the poles and defines the origin of latitude values as 0 degrees north or south.
(Source: ArcGIS dictionary)

Equidistant projection

A projection that maintains scale along one or more lines, or from one or two points to all other points on the map. Lines along which scale (distance) is correct are the same proportional length as the lines they reference on the globe. (Source: ArcGIS dictionary)

Explode

An editing process that separates a multipart feature into its component features, which become independent features.
(Source: ArcGIS dictionary)

Extrapolation

The inference or calculation of unknown values from values that are currently known; a method or technique of projecting or extending data or inferences beyond known values so as to arrive at conjectural knowledge of unknown data or inferences.
(Source: ArcGIS dictionary)