Definition
A map that shows the shape and elevation of terrain by means of contour lines — lines that connect points of equal elevation above a fixed reference, usually mean sea level. Spacing between the lines indicates the steepness of the terrain: lines close together represent steep slopes, while widely spaced lines represent gentle slopes or flat ground.
Plain English
A map that shows how high the ground is by drawing lines that link points at the same height. Lines bunched tightly mean the ground rises sharply; lines spread far apart mean the ground is fairly flat.
Context Anchor
Pilots may use contour maps during route planning, mountain flying preparation, or any time terrain height matters.
Derivation
From the French contour, meaning 'outline.' A contour map literally outlines the shape of the land by tracing equal-elevation lines.
Why Pilots Care
Shows terrain height so pilots can choose safe altitudes and avoid high ground, especially in mountainous areas.
Analogy
Think of a hill shown as a stack of thin slices. Each contour line is like the edge of one slice, showing where the hill is at that height.
Intuition Check
A contour map is not just a map with object outlines. In this context, the lines show land height and land shape.
Example Sentence 1
Before the cross-country flight through the valley, she studied the contour map to identify the highest terrain along her route.
Example Sentence 2
Before departure she checked the contour map to confirm no ridges exceeded her planned cruising altitude.