Online Reference For Body, Mind & Spirit

Term: Luis

The second letter of the Ogham tree alphabet, corresponding to the letter L and meaning "rowan."

The rowan tree was important to the Druids. Before going into battle, they would say incantations over fires made from rowan wood. It is not surprising then that Luis represents protection and the ability to distinguish good from bad.
SOURCE:  Omens, Oghams & Oracles, Richard Webster