v.1. To drop or descend from one location to a lower one: My coat got dirty when it fell on the muddy floor. The leaves fell upon the ground underneath the tree.
2. To occur at some particular point in time: My birthday falls on a Thursday this year. Their anniversary falls upon a Saturday this year.
3. To be passed on to someone, especially as a responsibility or burden: It falls on me now to maintain order here. It fell upon the president to solve the crisis.
4. To attack or beset someone or something suddenly and intensely: Insurgent forces fell on the unlucky patrol. A massive hurricane fell upon the coastal town.
5. To experience or enter into something, especially a negative state of affairs: The stockbrokers made a lot of money for a while, but fell on hard times during the recession. After he lost his job, he fell upon a difficult period.