sprack

From Middle English sprak, from Old Norse sparkr, sprekr (“lively”) and/or Old Norse sprækr (“lively”), from Proto-Germanic *sparkaz, *sprēkijaz, from Proto-Indo-European *sp(h)er(a)g- (“to strew, sprinkle”). More at spark.

sprack (comparative more sprack, superlative most sprack)

(UK, dialectal) lively, full of energy
- 1864, Jean Ingelow, chapter 1, in Studies for Stories: Emily's Ambition:
  She was apprenticed as a 'pupil teacher,' at fourteen years of age, and deemed to have a more than ordinary chance of doing well and getting on, for she was clever, and what is called 'sprack' in the part of the country where she lived.
- 1916, J. H. Morgan, Leaves from a Field Note-Book‎:
  "Yes, that I be, and I 'ave a little boy, he be a sprack little chap."

English