People who play the sport of bowling, or cricket players who throw the ball toward the batter.
From the verb 'bowl' (from Latin 'bulla' meaning ball) plus '-er' making it an agent noun. The word is used differently in American bowling versus British cricket.
The same word 'bowler' means completely different things depending on where you are—in America you're rolling a ball at pins, in Britain you're pitching a cricket ball—a perfect example of how English fractured into regional dialects.
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