noun

• (informal, uncountable) Nothing, or none.
  "The shipment was lost, so they had zero in stock."
• (mathematics) A value of the independent variables of a function, for which the function is equal to zero.
  "The zeroes of a polynomial are its roots by the fundamental theorem of algebra."
• (mathematics, algebra) The additive identity element of a monoid or greater algebraic structure, particularly a group or ring.
  "Since a commutative zero is the inverse of any additive identity, it must be unique when it exists."
• (slang) A person of little or no importance.
  "They rudely treated him like a zero."

adj

• (meteorology) Of a cloud ceiling, limiting vision to 50 feet (15 meters) or less.
• (meteorology) Of horizontal visibility, limited to 165 feet (50.3 meters) or less.
• (linguistics) Present at an abstract level, but not realized in the surface form.
  "The stem of "kobieta" with the zero ending is "kobiet"."
• (postpositive) Used in the names of foodstuffs, especially beverages, to indicate a version with no calories

verb

• (transitive) To set some amount to be zero.
  "They tried to zero the budget by the end of the quarter."