Douglas Harper's Etymology Dictionary
haggaday
mid-14c., "a kind of door latch," and said to be still the name for rings for raising thumb-latches in the north of England, appears to be what it looks like: what you say when you open the door ("have good day," as in the 1414 record of them as hafgooddays).
Usage examples of "haggaday".
Be you sorcerer or slave, beggar or baron, sophist or simpleton, prepare you to receive justice from Aufcash, Haggaday of the Hodgepoker.
What I need most is a bit of the cold air, the kind that naked Haggadays run around in.