1. a condition or capability needed by a user to solve a problem or achieve an objectiveContrast them with my definition. Interestingly, IEEE's first definition is nearly identical to mine, except that mine states the condition must be the least stringent one needed to solve a problem. It seems you could categorize all sorts of design and implementation details as requirements without this qualification.
2. a condition or capability that must be met or possessed by a system or system component to satisfy a contract, standard,specification, or other formally imposed document
3. a documented representation of a condition or capability as in (1) or (2)
Meanwhile, the discussion about requirements semantics continues and has spread to the Tyner Blain blog.