Green’s Dictionary of Slang

1. aggressive, crushing.

1832		Satirist (London) 9 Dec. 394/3: Mrs Peddle, in her efforts to turn them out, recived [sic] one of Mary’s ‘spiflicating’ hits.
1852		‘The Cadger’s Ball’ in Farmer Musa Pedestris (1896) 149: Spiflicating Charley Coker, / And Jane of the Hatchet-face divine.

2. remarkable.

1850		Fast Man 4:1 n.p.: Their toggery is terrifically astounding, truly spiflicating, licking Stultz into smash, and frightening the whole race of bum-case-constructors.
1871		Bradford Obs. 9 Feb. 7/1: ‘Spiflicating ain’t in “Webster”’.