in reply to My favorite silent English letter is:
I've changed my mind. I'd like to vote for the silent r in oh-so-many words in the standard English-English pronunciation. I can't call it British English because Scottish people often pronounce the r where the English don't. My dear departed Scottish father even said the r in "iron".
So my vote should have gone to the silent r that is a major feature of English-English pronunciation, the technical adjective being "non-rhotic".
PS I am fairly sure all the words in the poll would appear in any reasonable English dictionary so although they may have been borrowed from other languages they're English now. Someone once said: "The problem with defending the purity of the English language is that English is about as pure as a cribhouse whore. We don't just borrow words; on occasion, English has pursued other languages down alleyways to beat them unconscious and rifle their pockets for new vocabulary."