The phrase "hospital for the mentally sick" can be replaced with numerous synonyms that are more commonly used and considered less stigmatizing. One alternative is "psychiatric hospital," which specifically denotes medical care and treatment for mental health disorders. "Mental health hospital" is another option that emphasizes the broader scope of care for a range of mental illnesses. "Behavioral health center" may also be used, as it encompasses both mental health and substance abuse treatment. Other alternatives include "psychiatric center," "mental wellness facility," and "mental health institute." These synonyms allow for a more nuanced and compassionate approach to discussing mental illness and treatment.