In the middle of the Third Stanza, H.P. Blavatsky introduced "OEAOHOO" as the seven-fold Mundane Egg or the middle quaternary in conjunction with the lower triad. But "OEAOHOO" is much more than this. He is Adam Kadmon, a complete ten-fold Kosmic Being. H.P. Blavatsky had reached the point in The Secret Doctrine where she arrived at physical matter, the Milky Way Galaxy--"the matter we know." As a complete ten-fold Kosmic Being, she equated him with Parabrahman, where the two highest aspects of the twelve-fold Universe were enfolded within the highest Sephirah, Kether, or "Ain Soph on his Vehicle, Adam Kadmon" in The Secret Doctrine 2:730. But she also equated him with "manifested ONE LIFE." He is the upper triad, the middle quaternary, and the lower triad in harmonious unity. The "Light" in him is the same "Omnipresent Spiritual Ray" that calls the cosmic matter we know to begin its "long series of differentiations."
It is this cosmic matter, even in the Maha-Pralaya, that is "perceivable" to the "eye of the perfect Bodhisattva." And so the Dhyani-Buddhas and Bodhisattvas can actually see our physical universe come into manifestation. This "matter" is "cool" at first and gradually, as a result of the "first reawakening of cosmic motion" after being expelled from the laya center, scatters into Space in "clusters and lumps, like curds in thin milk"--the beginnings of the Central Suns, their attendant Suns, and solar systems on our physical plane.
"OEAOHOO" is the "Incorporeal man who contains in himself the divine Idea." He is the "Bright Space, son of dark Space" that corresponds to the "Ray dropped at the first thrill of the new 'Dawn' into the great Cosmic depths, from which it re-remerges differentiated as Oeaohoo the younger, (the 'NEW LIFE'), to the end of the life-cycle, the germ of all things." So Oeaohoo is the potential point thrilling through the dull black ground until he actively emerges as the 3rd Logos overseeing the Mundane Egg when he becomes Oeaohoo "the younger" or the "Blazing Dragon of Wisdom." The Dragon of Wisdom is the "Verbum of the Thought Divine" who contains "the Seven Creative Hosts." In this sense, he is equivalent with the Buddhist "Avalokitesvara," or the "lord" who is "perceived," according to G. de Purucker's definition in the Occult Glossary on page 15.
Sources:
H.P. Blavatsky, The Secret Doctrine (Pasadena: Theosophical University Press, 2019).
G. de Purucker, Occult Glossary (Pasadena: Theosophical University Press, 1996).

(Photo by Aleksei on Unsplash)