What is the latin or greek root of the word groom?

Answer 1

The word English groom has neither Latin or Greek history. It comes from Middle English grome, meaning a boy or male child (first recorded about 1200 AD). By about 1300 the meaning was "a youth or young man". Its origins are therefore the Germanic dialects of northern Europe.

This meaning slowly evolved into the sense of "a servant, particularly a young servant responsible for caring for horses" - in this sense it does not appear before the 17th century.

The word bridegroom has a different history (but still from the Germanic dialects) - the second element is Old English guma, a man.