* Temperature: Below zero degrees Celsius or Fahrenheit refers to temperatures colder than the freezing point of water.
* Numbers: Numbers below zero are negative numbers.
* Altitude: Below zero altitude means you are below sea level.
* Other contexts: "Below zero" can be used metaphorically to describe things that are very low, bad, or negative. For example, "His spirits were below zero after the news."
Could you please provide more context so I can give you a more specific answer?
