A: Excuse me, can I use your phone for a second? Mine is out of juice.

B: Sure. I always pack three spare phone batteries with me on my climbing trip so I don’t run out of juice.

Note: Literally referring to the natural fluid, fluid content, or liquid part that can be extracted from a plant or one of its parts, especially of a fruit, juice can also refer to the natural fluids of an animal body, and by metaphor, essence, strength or vitality. As a slang term, “juice” can mean “electric power.” If a phone is out of juice, it’s out of electricity. If a person is out of juice, he or she feels low in energy. If your car is running out of juice, it’s low on gas.