what’s the difference between -ists and -ologists in medical fields?

Question

On one hand you have pharmacist, dentist, anethsacist, psychiatrist, etc. One the other you have cardiologist, urologist, neurologist, etc.

Is there a rule for this, or just what sounds better? Could you have a neuralist or a psyciatrologist?

In: Other

Answer 1

Let’s take the word cardiologist (καρδιολόγος) for example. It derives from the two following greek words:

-καρδιά (carthia ,pronounce the ‘th’ as you would pronounce it in ‘that’) , meaning heart

-λόγος (logos , pronounce the ‘g’ as the ‘w’ in ‘what’), meaning speech

So a cardiologist is someone who talks about the heart. Now it seems that every greek profession that ends in -λόγος , was turned into ologist. As for the words that don’t , they were other arbitrarily implemented with ist or they derive from some other language.