Hello Frederic, "Fetch" has two possible meanings: 1) to go after and bring back (someone or something) --- Wait here while I fetch the doctor. 2) to be sold for (an amount of money) --- The house fetched more than we expected. https://www.learnersdictionary.com/definition/fetch If you use "fetch" in the first sense, it is a synonym of "pick up." "Pick up," however, has other possible meanings that are *not* equivalent to "fetch." They are: 1) to lift (someone or something) from the ground or a low surface --- He bent to pick up his hat. 2) to let or put (people or things) into or onto a car, bus, ship, etc. --- The ship will be picking up more cargo at the next port. 3) (chiefly US) to make an area clean and organized by removing trash and putting things in the proper places --- The children worked together to pick up the toys. https://www.learnersdictionary.com/definition/pick I hope that this answers your question. All the best, Christine

For me, in U.S. English, "fetch" is primarily used to describe what my dog does when I throw a stick for him.

Hello Frederic! To "pick up" in this context (there are quite a few other meanings), means to physically go to a place to collect something that has been left somewhere, or that is needed. To "fetch" in this context means to go and pick something (or someone) up and bring that thing or person back. So the difference is that the first one is just to collect and the second is to collect and bring back. I hope that helps!

I imagine you can't pick up something that is on a high shelf, and you can't fetch something that is right in front of you on the table.