Tipping at Windmills

[Sevil]

What does the expression 'tipping at windmills' mean and how did it originate? Thank you!

[Quizmonster]

'Tilting at windmills' is the more usual expression and it comes from the great Spanish tale of 'Don Quixote' by Cervantes. Quixote was a knight errant in search of adventures and - never having seen a windmill before - he thought one was a gigantic enemy. Consequently he rode at it in an effort to 'tilt' it with his lance as was the custom in jousting contests of old. Nowadays, the phrase is just a reference to attacking purely imagined foes.