doolally (adj.) Look up doolally at Dictionary.com
"insane, eccentric," British slang, by 1917 in the armed services and in full doolally tap (with the Urdu word for "fever"), from Deolali, near Bombay, India, which was a military camp (established 1861) with a large barracks and a chief staging point for British troops on their way to or from India; the reference is to men whose enlistments had expired who waited there impatiently for transport home.