Gracious
Xaine is a modern phonetic variant of the name Zane, which is itself a derivative of John. It carries the traditional meaning of divine favor while utilizing the contemporary 'X' initial for a more unique visual appeal.
Less common today
Xaine isn't in the latest US Top 1000. It last peaked at #6,671 in 2018.
US births per 5-year period, 1990βpresent (SSA data).