Slap-happy is a compound word which has retained its hyphen, though it is sometimes seen rendered as two words without the hyphen. We’ll look at the meaning of slap-happy, where the term came from, and its use in several sentences.
Slap-happy describes someone who is overly giddy, someone whose intellect or self-control is impaired. A person might be slap-happy due to being overly stressed, overly tired or overly worked. Slap-happy may also describe someone who is irresponsibly happy and carefree. The final definition of slap-happy describes someone who is impaired because of repeated blows to the head. This is the original meaning of the term slap-happy, first appearing in the 1930s. Slap-happy comes from the sport of boxing, first describing boxers who have taken too many blows to the head and thereby sustained permanent cognitive injury. The word quickly made its way into the mainstream of American culture to be used figuratively. A good indication of mainstream American slang may be found in the early Looney Tunes cartoons. In 1940 the company released a cartoon called Slap Happy Pappy, starring Porky Pig. Rather than describing a medical ailment, slap-happy is most often used to describe someone who is jet-lagged, has otherwise been deprived of sleep or has been working on a problem for too long without a break.
William F. McGregor Jr., the derby’s managing director, is still a little slap-happy after he and his derby crew took a working over from the biggest mob of sports anglers ever to descend on this city. (The Daily Astorian)
“There would be times when we would be so slap happy and laughing on the way to practice, belting out country songs, or just laughing at the silliest of things,” Schmitt said. (The Detroit Free Press)