Pecksniffian \pek-SNIF-ee-uhn\ , adjective;
1. Hypocritically and smugly affecting benevolence or high moral principles
Like frabjous, lilliputian, and more, the origin of this word is an author's creativity. This one we can attribute to the great Charles Dickens. From January 1843 to July 1844 he wrote a monthly serial called 'The Life and Adventures of Martin Chuzzlewit' which included a greasy hypocrite named Mr. Pecksniff. Thus pecksniffian was born. It is first attested in 1851.
Today's word and the first definition were both taken from Dictionary.com's 'Word of the Day' for Monday, June 6
Etymologies come from the Oxford English Dictionary and/or Etymonline.com