expression, noun
uninvited guest
A set phrase meaning a guest who was not invited, often with a negative or unwelcome connotation. The ざる is a classical negative form of 招く, giving the phrase a slightly formal or literary feel.
彼は招かれざる客としてパーティーに現れた。
He showed up at the party as an uninvited guest.
招かれざる客が突然訪ねてきた。
An uninvited guest suddenly came to visit.