adjective
Possessed; raving; isolated from reality.
Taken away; also sneaked in surreptitiously.https://books.google.com.au/books?id=K_lmAAAAcAAJ&pg=PP26&dq=arreptitious&hl=en&sa=X&ved=0ahUKEwjy5JPExMbRAhULkZQKHR6-AYs4ChDoAQgxMAM#v=onepage&q=arreptitious&f=false