The phrase "wast in cahoots" is an archaic way of saying "you were in collusion or conspiring with someone." The word "wast" is the second-person singular past tense of "be" in Middle English. It is pronounced as /wɑːst/. Similarly, "cahoots" is a term used to describe a partnership or secret alliance. The word is pronounced as /kəˈhuːts/. The phrase is rarely used in modern English but can be found in literature and older speeches.