What's the meaning of the phrase 'Okey dokey'?
'Okey-dokey' is just an extended form of 'okay'.
There are some alternative meanings, coined in the late 20th century and limited to the USA, e.g. 'absurd or ridiculous' and 'to swindle or deceive'.
What's the origin of the phrase 'Okey dokey'?
This little phrase is a variant of okay. It is 20th century American and first appears in print in a 1932 edition of American Speech.
There are several alternative spellings - okay-doke, okey-doke, okee-doke, etc. In addition to these is the comic version that has brought the phrase back to popular attention in recent years - The Simpson's Ned Flanders' 'okely-dokely'.
All of them are just a perky reduplicated variants of okay, utilizing that favourite device of two-word phrases - rhyming. As a reduplication it is properly spelled with a hyphen, although it is often given without.
Like okay, 'okey-doke' is used to indicate that all is well, e.g. 'everything is okay here', but may be used when responding positively to a request. That is exemplified in this piece from Colin MacInnes' book City of Spades, 1957:
"One Guinness stout, right, I thank you, okey-doke, here it is."
See other reduplicated phrases.