Q:

Difference between words 'stench' and 'stink'

What is the difference between 'stench' and 'stink', both used as nouns and smells? I want the  olfactory distinction of these words. I am very much aware of the other meanings of stink but that is not what I want.
For example:

There was a stench in the bathroom.
There was a stink in the bathroom.

What's the distinction here?

A:

The Oxford dictionary describes stench as:

A strong and very unpleasant smell

It describes stink as:

A strong unpleasant smell; a stench

So according to this, both words mean the same. I found also that both have the same etymology. They arise from the Old English stenc.
I was wondering if there were a shred of difference in their meanings but I am not able to find any. An English professor, very long ago, had told me that no two words in the English language have the same meaning. They may have similar meanings, but not same. But here we seem to have refuted his ideology.

