Designing a vocabulary for geographical features

Question

I want to draw a map of a fictional world resembling Europe in climate and basic geographic features (so there are rivers and lakes, alpine mountains, mittelgebirge, marsh lands and bogs, some plains and forests).

I am thinking of dithematic words (similar to typical endocentric compound words where the second part denotes the general feature and the first part gives a distinguishing detail), so I need words for river, lake, mountain, marsh, bog etc. and some determining words.

However, I want the words to look naturalistic and not overly schematic. What techniques can I use to make the geographical features look naturalistic?

EDIT: Assume that I have already designed a phonology for my conlang stub, and that I have already some phonotactics and candidate root words. What I am interested in is some natural looking variation of the names to generate.

Answer 1

There are many factors that make actual real-world placename not look schematic (unless, maybe, you're looking at Japanese placenames...)

Have many different etymological sources from names

In practice, names have a lot of forms, and the younger the names, the more varied the forms: religious names (i.e. saints) and feasts, people names ("X's place", "X's farm", "X's dwelling" are all very common sources of names, but just look at how many us towns are named after female given names!), other placenames (e.g. Athens, Georgia), etc.

Layer the source languages

European names show variety at least in part because the names comes from many layers of languages: France has names in modern French from Germanic, Celtic, Romance (French, Old French, Spanish, Latin roots), and pre-IE languages. In England you have Scottish, Celtic, Old English, Normand and Old Norse/Danish names.

People really don't pay that much attention to the form of a word

A simple example is how common "new town" is as a name: Newton, Newcastle, Villeneuve, Neuville, Villanueva, Villanova, Neustadt, Neuburg, Novgorod, Novohrad, Nevşehir, Yenişehir... All of these are fairly common city names in their respective languages. "Blue Lake" may not feel original, but to te people who come later, it's just a name like any other. The same as we don't really notice "Rowan" or "Rose" are common nouns once they are people's name.

Answer 2

The first thing is: Design not only one word for each geographical feature, use several of them. To give some examples from a natural language (German in this case): A mountain may have a name in -berg (which is frequent in the mittelgebirge) but also -spitze, -horn, -kopf, or -kuppe. Some beacon mountains have names of their own without an element meaning "mountain" (e.g., Brocken, Großer Belchen, Kahler Asten, or Eiger). Similarly, cities are not just -stadt "city", but there are also cities in Germany with names in -burg, -berg, -heim, -reut, -furt, or -hafen.

The second thing is: Hydronyms are special. The names of larger rivers often reflect an older substrate and are not taken from the current language of the place and don't have any transparent meaning. Examples are Potomac, Arkansas, Mississippi, Missouri in the USA or Thames, Rhine, Rhône, and more in Europe.

With this in mind, the names on the map should show some interesting variation.