From Longman Dictionary of Contemporary Englishtilt at somebody/something phrasal verb1 CRITICIZEto attack someone in what you say or write2 tilt at windmills to waste time and energy attacking an enemy that is not real → tilt→ See Verb table
Examples from the Corpus
tilt at windmills• But Woodhead's art was to tilt at windmills.• I felt that just by being there I was tilting at windmills.• For the past 12 years the Government have behaved like latter day Don Quixotes tilting at windmills and all the other renewables.• Commitment and dedication remained, but tilting at windmills had to stop.• Manning admits he was tilting at windmills in trying to change the nation's prison system.• While the Hague event may seem to be an exercise in tilting at windmills, the opposite may also be true. 