To thrash, handle roughly, destroy, or annihilate.
Etymology: Most references imply the word originated in the 1700s...yet some say it originated as British school slang; the exact source of the word seems unclear.
From a book on slang (found in Google books), "To spiflicate a thief is to spill him, or betray the subject of his roguery."
I ran across the word in a recent purchase (The Life of the Grasshopper by Jean-Henri Fabre): "All said, I prefer the spiflicating virtues of the tigno to the old naturalist's imaginings" [of a lost child being pointed in the right direction by a mantis]. (The tigno is a term for a praying mantis nest; apparently there are references to the nests being gathered and used as folk remedies for toothaches and other ailments.)