Gracious
Jancy is a rare diminutive or variant of Jane or Janey, which ultimately derives from the Hebrew name Yochanan. It shares the same etymological root as John and Joan, signifying divine favor. While it has occasionally appeared as a surname, its use as a first name is modern and quite uncommon.
Less common today
Jancy isn't in the latest US Top 1000. It last peaked at #8,198 in 1993.
US births per 5-year period, 1990βpresent (SSA data).