Yee : O.U. ~ a pseudo rune expressing the "Y" sound, having been in use over 1,000 yrs ago. Many use Isa to express the vowel sound, and Jera to express the consonant sound, although this oft results in some confusion.
Yggdrasil : O.N. the Steed of Ygg can be seen, in one sense, as the human spine, yet, at the same moment, include the all-encompassing Omniverse of Norse Mythology. See the various entries throughout the Word Hoard such as Functions, Nine Realms, and Worlds-All-Wide for varying input on this subject. Somewhere's within this Site there's a greater amount of info on the subjectů
O.N. ~ meaning the essential glow of life. It can also be used to mean the healing warmth of the Sun, or that of love; for example, "to bask in the YlR of Sunna", could mean "to comforably expose oneself to the heat of sunlight and enjoy the warmth." Of course, other connotations may be seen by some.