Etymology

From Danish or Norwegian persille, from Medieval Latin petrocilium, from Latin petroselinum (spelt also petroselinon),
from Ancient Greek πετροσέλινον ‎(petrosélinon, “parsley”), from πέτρος ‎(pétros, “rock, stone”) + σέλινον ‎(sélinon, “celery”).

See also Icelandic steinselja.