Definition of "wellnigh"

wellnigh

adverb
not comparable
1. Alternative spelling of well-nigh.
  Quotations
  […] Huck’s confidence in the human race was wellnigh obliterated.
  1876, Mark Twain [pseudonym; Samuel Langhorne Clemens], chapter XXIV, in The Adventures of Tom Sawyer, Hartford, Conn.: The American Publishing Company
  Athens especially never forgave the defection which had wellnigh involved her in hopeless ruin.
  1879, F. D. Morice, Pindar, chapter 10, page 161
  Five years ago the officers determined to build a new mess. There was only one objection to the fulfilment of this wish: the regimental coffers were wellnigh empty.
  1910, Erwin Rosen [pseudonym; Erwin Carlé], “A Hundred Thousand Heroes—A Hundred Thousand Victims”, in In the Foreign Legion, London: Duckworth & Co. […], page 137