I'm just a learner like you, but I'd like to give it a shot.
I usually associate the word condiment with the free packages in a restaurant that add flavor to your food. e.g. ketchup packages, salt, pepper, etc. But where I live, I have never heard of this word used in home cooking. But I can be wrong.
Seasoning is anything that you use to add flavor to y
I would tend to use the word condiment for something that is added at the table (ketchup, mustard, mayonnaise,) while seasonings can be added either during cooking or at the table (paprika, nutmeg, rosemary, salt, pepper).
I'm sick and tired of it. I've spent whole day translating a cookbook. I'm dead. Imagine, in Croatian there is only one word for these four terms, perhaps two, but... To me, spice and seasoning are the same, whereas condinment is more like an addition to a meal. And dressing, isn't it liquid? Not necessarily, I guess..argh! Thank you all for your effort, you are great, If you ever