The key concept, always missed, contained in this word, or equation, is that the "seal" is a reverse imprint of the energy making the seal. The Sepher Yetsira is saturated with this concept, which is why it is never understood, because it would upset too many belief systems and cause catastrophic change. Why else would the reverse imprint of the Aleph-Bet in By thirty-two Wondrous Paths at the beginning of a book about the alphabet, never be recognized? Or that Sephirot and Belimah are the same letters, with a Bayt for an Aleph? And, of course, understanding of the Sepher Yetsira goes downhill from there, and the meaning of all the engraving, carving, cutting, chiseling and sealing, let alone all the double equations and pairings of energy and their integration in the "One Name," is lost.
Seals are used twice in the Sepher Yetsira, once in 1:13 where the six outer directions are sealed with his Great Name (and above is sealed twice, another overlooked key fact), and again in Verse 3, where the great "secret" of the reverse imprint mev phaylay is missed again, and the six seals or rings of 1:13 seal/are sealed with permutaions of the Three Mothers Aleph-Mem-Sheen which engender the Fathers of manifestation Air-Water-Fire in the spheres of Universe, Change and Soul, forming the axes of existence, life and experience, with the qualities of male and female.
But again, the important thing to see is the impact of the unseen as it seals and engraves and carves all that we can see.
Tav-Mem is perfection, the goal of consciousness/unstructured energy.
Chatham/Chotam/Hhatam : to seal, seal up, affix a seal (Qal) to seal, affix one's seal to seal up, fasten up by sealing (Niphal) to seal (Piel) to lock up (Hiphil) to be stopped
Usage: 14 times in the Old Testament - Song of Songs