Gracious
Jance is a rare variant of Jan or John, ultimately derived from the Hebrew name Yochanan. It functions as a phonetic variation or a surname-turned-first-name, carrying the traditional meaning of divine favor.
Less common today
Jance isn't in the latest US Top 1000. It last peaked at #7,124 in 1990.
US births per 5-year period, 1990βpresent (SSA data).