Aaron's rod refers to any of the walking sticks carried by Moses' brother, Aaron, in the Torah. The Bible tells how, along with Moses's rod, Aaron's rod was endowed with miraculous power during the Plagues of Egypt that preceded the Exodus. Later, his rod miraculously sprouted blossoms and almonds to symbolize God's choice of Aaron and his tribe for holy service.

Hortus conclusus is a Latin term, meaning literally "enclosed garden". Both words in hortus conclusus refer linguistically to enclosure. It describes a type of garden that was enclosed as a practical concern, a major theme in the history of gardening, where walled gardens were and are common. The garden room is a similar feature, usually less fully enclosed.