Condition refers to a term with a number of biomedical meanings, among them are:
1. An unhealthy state, such as in "this is a progressive condition."
2. A state of fitness ,
such as "getting into condition."
3. Something that is essential to the occurrence of something else; essentially a "precondition."
4. As a verb: to cause a change in something so that a response that was previously associated with a certain stimulus becomes associated with another stimulus; to condition a person, as in behavioral conditioning.
List of books: Condition