maylit, There is no such thing as a "beejeeber". The dictionary lists an older form "bejabbers" It is a mild form of swearing. "Bejeebers" or "bejabbers" is a euphemism for "beJesus". He scared the bejeebers out of me. She knocked the bejeebers out of him with one punch. It is similar to saying "hell" as in "He shook the hell out of it." or "It scared the hell out of him."

I think it just means general 'contents'. People might say "it frightened the bejeebers out of me" instead of "it frightened the life out of me". It doesn't mean any specific physical or material item. Hope it helps!

Denis doesn't know Victorian English. Beejeebers is a euphemism for one's wits. Typical uses include: beat the beegeebers out of you scare the beejeebers out of me confuse the beegeebers out of me