bigwig [E18th] People of importance in the 17th and 18th centuries wore large *wigs that covered their heads and came down to their shoulders. These were the original ‘big wigs’. In Britain this type of headdress can still be worn by judges, the Lord Chancellor, and the Speaker of the House of Commons. In the 18th century bigwig began to refer to the person wearing the wig, and the word has outlived the fashion.