I can understand why they seem similar or even the same, since pronunciation is a matter of correctness and enunciation a matter of clarity. To the listener either can make understanding good or bad.

I think for me the difference is often one of context. I use "pronunciation" more in the context of language learning, and"enunciation" in the context of evaluating someone who is fluent in the language.

Examples: The Spanish have a lot of trouble saying words like "Spain" - the "sp" at the beginning makes them want to say "Espain" until they are faily advanced because of the biases in Spanish. Now a Spaniard could anunciate very clearly "E-Spain". I would have no doubt what I was hearing. However the pronunciation is wrong. 

With myself, when I am lazy in my speech people accuse me of "mumbling". They do not think I have how to pronounce a word. They are accusing me of not speaking clearly - anunciating. So they may not be sure if I think the cookie is better or bitter. Not because I have pronounced a word incorrectly but because I did not anunciate the vowel clearly.

When natives say "gonna" it is a poor anunciation of "going to". It is not considered bad pronunciation because most natives do this.

The first man on the moon, Neil Armstong, is forever locked into an anunciation issue. Most of us heard him say "a small step for man" when he should have said "a small step for a man", which makes much more sense. Because of his anunciation it will forever be debated which sentence he really said. 

If you have a stroke you may have trouble speaking clearly in your own language. hat is bad anunciation since everyone knows you are trying to say the correct thing.

I've never even heard of 'enounce' - that's a new word for me!

I'd use 'enunciate' and 'enunciation' about speaking clearly, usually in one's own language. School poetry-reading competitions come to mind. For me, it suggests standing straight, breathing well, opening your mouth wide, not mumbling or slurring your words, nice clear vowels and crisp consonants, and so on. Not to be confused with 'annunciation'. :)

'Pronounce' and 'pronunciation' are used more in a foreign language context. They're  less about clarity and more about how particular words and phonemes need to sound, according to the phonological rules of a language or language variant. Among English speakers, it's sometimes an issue along the lines of 'Do you pronounce the 't' in 'often' or not?' i.e. how it should be said.

Robert

Thank you for your detailed comments.

Your understanding and thorough explanations are in sync with my understandiing and the distinctions between the two words.

I guess my only concern was the result of seeing that they are synonyms, while their definitions strike me as dissimilar.

Just to avoid any confusion*, (I'm sure you meant to type enunciation) annunciation is either a religious proclamation or an announcement. 

* I'm sure I've already made this discussion confusing enough as is :)

zaeanderson and SuKi

You have both expressed the same notions and usages... thank you both.

I had also thought along the same lines, but I was a tad unsure because they were listed as synonyms, and yet they strike me as somewhat less than synonymous.

Yup, enounce (rare) does appear to be the same as enunciate.

This lazy Canadian boy does pronounce 'often' without the 't'... bad boy :) 

Thank you both...