An activity involving physical exertion and skill that is governed by a set of rules or customs and often undertaken competitively. b. often sports (used with a sing. verb) Such activities considered as a group: Sports is a good way for children to get exercise.
Rust is Iron Oxide. Hence, any warnings concerning the ingestion of iron may apply. Ingesting too much iron, whether it be via rust, suppliments, or otherwise, can lead to unpleasant symptoms including nausea and vomiting. Long-term side affects such as liver damage can be associated with excessive iron intake.
Rust can be a minor annoyance if it stains your clothing or your tools, or it can be a major disaster in buildings and infrastructure. Rust is the result of an electrochemical reaction that is really like a battery; Iron turns to iron oxide with water as the electrolyte, actually making electricity in the process.