What are some examples of body fluids?
Blood, urine, cerebrospinal...
A body fluid is any fluid that is either secreted or excreted from the body. That is to say that it is either pushed out of a cell to another compartment within the body (secretion), or it's pushed out of the body into the environment (excretion).
There are many different types of fluids in the body, each with a generally specific job. Blood, for example, is the transportation medium that carries the nutrients to the many cells in an organism. Urine is a collection of waste that your body has decided that it doesn't need.
Cerebrospinal fluid, or CSF, has the responsibility of protecting the cortex of the brain.
Breast milk is also a body fluid, as it's excreted from the body.
Saliva is another one. It's relatively acidic, and it's charged with assisting in the breakdown of food for digestion.
There are many, many more, but here are a few more examples: