A slang term originally used by cattle herding cowboys to get their cattle to move faster. Elongated form of the the word yippee, which is used when a person is exuberantly happy about something. Has been used in numerous songs including Country Western, Hip Hop, and even Frank Sinatra used the term in a song. The term was made ultra-popular by actor Bruce Willis, who has used the term in each of his Die Hard film roles. In fact "yippeekyay mother fucker" has become his catch-phrase. Although we come across numerous different spellings of the word, we all understand it's meaning when we hear it.
Hans Gruber's reference to John McClane as a "cowboy" in Die Hard instigated McClane to use the phrase "yippeekyay motherfucker!" In other words "Yee- ha, let's get it on asshole."
Fogey/fogy /fougi/ sl. (early 18C+, orig. Scot) old-fashioned, stuck-in-the mud.
Person with old fashioned ideas which he is unwilling to change: Come to the disco and stop being such an old fogey!
You think me an old fogeyand an old tory, his thoughtful voice said. I saw three generations since O’Connel’s time. I remember the famine. Do you know that the orange lodges agitated for repeal of the union twenty years before O’Connel did or before the prelates of your communion denounced him as a demagogue? You fenians forget some things. (James Joyce, Ulysses. Penguin Books,1992. p. 38)