From Longman Dictionary of Contemporary Englishchurn somebody/something ↔ up phrasal verb1 DAMAGE churn something ↔ up to damage the surface of the ground, especially by walking on it or driving a vehicle over it The lawn had been churned up by the tractor.2 MOVE/CHANGE POSITION churn something ↔ up to move water, mud etc around violently The oars had churned up the mud, clouding the water.3 British EnglishUPSET to make someone upset or angry Though she looked calm, in reality she was churned up inside. → churn→ See Verb table