What does ADH secretion, inappropriate mean?

ADH secretion, inappropriate meaning in Medical Dictionary

a condition which causes the inability to make dilute urine and imbalance of liquids and electrolytes within the body, particularly lowering bloodstream salt. Symptoms include sickness, vomiting, muscle mass cramps, confusion, and convulsions. This problem might occur with oat-cell lung cancer tumors, pancreatic disease, prostate cancer, and Hodgkin's illness, among various other problems. Also called problem of unacceptable ADH secretion or SIADH.