WEIGH ON

v. 1. To be a weight or pressure on; be heavy on. The pack weighed heavily on the soldier's back. 2. To make sad or worried; trouble; disturb; upset. Sadness weighed on Mary's heart when her kitten died. John's wrongdoing weighed upon his conscience. The teacher's advice weighed upon Tom's mind. 3. To be a burden to. His guilt weighed heavily upon him.