For example what is the origin of name Catherine?
Etymology Dictionary says that:
it's from French Catherine, from Medieval Latin Katerina, from Latin Ecaterina, from Greek Aikaterine. The -h- was introduced 16c., probably a folk etymology from Greek katheros "pure." The initial Greek vowel is preserved in Russian form Ekaterina. As the name of a type of pear, attested from 1640s. Catherine wheel (early 13c.) is named for St. Catherine of Alexandria, legendary virgin martyr from the time of Maximinus who was tortured on a spiked wheel. Her name day is Nov. 25. A popular saint in the Middle Ages, which accounts for the popularity of the given name.
So the origin of this word is Greek? or Latin? or French?
How to find out?