My dishwasher does not work like a human being, it works like a dishwasher. If my dishwasher spoke English, I might be inclined to agree with you.
Yes I do all of my dishes by hand. If I had a large chunk of ice, that’s exactly how I would keep my food cold. Do I... probably. My definition of robot is a machine with feet and hands that walks around and does stuff - not a stationary object void of opposable thumbs.
In closing: all Wiccans are witches, but not all witches are Wiccans. Furthermore: all robots are machines, but not all machines are robots. So you can stick your dictionary in the orifice of your choice.
When you wash dishes by hand, do you: A) Wash, Rinse, Dry? or

Let your cats lick them clean?
If you chose A) Wash, Rinse, Dry... that's exactly how a dishwasher works.
If you chose

Let your cats lick them clean... you have issues.
So, by saying a robot has to have feet and hands and walks around and does stuff... and it has to have opposable thumbs, how do you explain the robots that paint cars at the manufacturing plants? They are simple arms with a paint spray gun attached to the end. They are robots, though.
True, not all machines are robots... but you said it yourself... all robots are machines. You must have a greater understanding of the inner-workings of the English language than the people that write the dictionaries. Maybe you should write one yourself. I'll give you some advice though, since you implied that I should shove my dictionary up my ass... Don't quit your day job.