A spontaneous event which is associated with wetness like a puppy licking your face. Could also be used to describe any kind of unexpected, yet warmly received, gesture. Can also be used sarcastically to describe either mishaps or actions which could result in a mishap like leaving a banana peel on the floor (e.g., "Bro, nice slapperdoodle in the kitchen! Clean that shit up.")
"Look at little Charlie playing with the puppy! Aw, he just got a slapperdoodle!"
"The slug left a bunch of slapperdoodles on the front porch."
"Just as the night was coming to an end, she pulled out some LSD from her purse. The universe was giving me slapperdoodle all day long!"
(adj) Used to describe a person who seems to have some type of sixth sense when it comes to not getting caught up in some illegal and/or immoral deeds. Very difficult, hard, and/or burdensome to catch, if at all; very slick, clever, and/or cunning.
Jerry was the most slippery son of a bitch in the neighborhood. When the police raided the pool hall last Friday everyone in that mother fucker was arrested and went to jail. Everyone that is except Jerry's slippery ass, mother fucker's charmed I tell you.