Koryn is likely a variant of Corinne or Corin, from Greek roots associated with a maiden.
Koryn is a creative spelling of Corin or Corinna, names with roots deep in classical antiquity. The foundation is the ancient Greek word 'korē' (κόρη), meaning 'maiden' or 'girl' — the same root that gives us the name of Persephone in her guise as the goddess of spring, often referred to simply as Korē in Greek myth. This connection to the maiden goddess of seasons and regeneration gives the name an elemental resonance that has endured for millennia.
Corinna of Tanagra was a celebrated Greek lyric poet of the fifth or fourth century BCE, said to have been a teacher or rival of Pindar and praised for her ability to write in the Boeotian dialect with unusual expressiveness. Though only fragments of her work survive, her name carried literary prestige through the Renaissance, when poets including Ovid used 'Corinna' as a pseudonym for their beloved in erotic verse — Ovid's 'Amores' cycles around a Corinna who may or may not have been a real woman. The name thus acquired associations of poetic beauty and romantic idealism.
The spelling Koryn arrived in the late twentieth century as part of the broader movement to individualize traditional names through phonetic respelling. It shares the same sound as its classical ancestor while signaling a modern sensibility. It appeals to parents who want classical roots without the conventionality of the standard spelling.