645 meanings? It's the word "run." I remember learning to read that word in the first grade in my Dick and Jane reader. "See Spot run" has become a catch phrase.
Run, Forrest, run!" (Click to watch the video of Forrest Gump's long, long run, which lasted 3 years, 2 months, 14 days, and 16 hours, he says.)
That's only ONE kind of running. Editors of the Oxford English Dictionary say "run" is the most complicated word in the English language. Think of these other uses of the word: run up a large debt, run a company, run to the store (in your car, not on foot), run out of mayonnaise, the long run of a Broadway musical, run your children to school, a trial run, and a run on banks in the 1930s. Water can run over the brim of a cup, and waiting to be seated at a good restaurant may run half an hour or more. And now I've run out of pithy examples, except maybe a running joke, which differs from a running total.