American here, I'm going to challenge myself to remember as many as I can.

Set: A group of things that go together.

Set: Letting a dessert cool in the fridge

Set: A stage for a play or film

Set: A command to put something somewhere

Set: A part of Tennis

...

5/704 isn't so bad, right?

Edit: looking up the definitions shows a lot of sub-definitions that essentially have the same meaning. I don't think it's appropriate to say that the word has 435 meanings when "set a course" and "set a fire" are basically "start a thing," yet they're listed as different definitions. The are many many of these cases even just on Google's definition blurb.

But I'm no dictionary expert so...