The day exactly one month after your actual birthday. This is usually celebrated when one's actual birthday has been inadvertently missed, and therefore calls for much more rigourous partying. Example: We better go get a couple of kegs. It's hunky dory day!
HUNKY DORY DAY
Meaning of HUNKY DORY DAY in English
Slang English vocab. Английский сленговый словарь. 2012