WBC or White Blood Cells: Cells found in the blood and tissues that aid in fighting infections and making antibodies for the immune system's attack against disease. There are several types of white blood cells including neutrophils and lymphocytes. The normal WBC count is 5,000-10,000.

Wheezing: A whistling noise in the chest during breathing when the airways are narrowed or compressed, such as in asthma or bronchialitis.

Withdrawal symptoms: Abnormal physical or psychological features that follow the abrupt stoppage of a drug that can produce physical dependence. Common withdrawal symptoms include sweating, tremor, vomiting, anxiety, insomnia, fever, irritability, and muscle pain.