Definitions of common terms

DEFINITIONS
Before reading further, it is important that you understand the terms used in describing the ground, as they must have the same meaning both to the speaker and the listener; otherwise there will be misunderstanding. Many terms such as hill, valley, mountain and stream are in common use and need no definition. However, the topographical terms given below are those which are fairly well used, but not always fully understood:
a.	Basin - an area of fairly level ground surrounded or nearly surrounded by hills; or the area drained by a river and its tributaries.
b.	Col - see Saddle below.
c.	Crest - the highest part of a hill or mountain range. That line on a range of hills or mountains from which the ground slopes down in opposite directions.
d.	Divide - the line along a range of hills from which the water flows in opposite directions, eg, the continental divide.
e.	Escarpment - the steep hillside formed by a sudden drop in the general ground level, usually from a plateau.
f.	Gorge - a narrow stream passage between steep rocky hills; a ravine with precipitous sides.
g.	Knoll - a small knob-like hill.
h.	Left/right bank - the bank of a river on the left/right facing downstream.
i.	Plateau - a table land; an elevated region of considerable extent, generally fairly level.
j.	Re-entrant - a valley or ravine, usually between two spurs, running inwards towards the hill or mountain top.
k.	Ridge - the line along a hill or range of hills or mountains from which the water flows in opposite directions; a divide; sometimes the crest of a line of hills as it appears along the horizon.
l.	Saddle - a depression between adjacent hill or mountain tops: also called a col.
m.	Spur - a minor feature, generally in the form of a ridge running out from a hill or mountain.
n.	Watershed - the line separating the water flowing into two different river systems; the edge of a river basin.
More details about some of the more common features covered above is given at in the section on Contours.

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