Nirvana-Mastaka (devanāgarī: निर्वाणमस्तक, from nirvāṇa, "blown out" and mastaka, 'head, chief') is a Sanskrit term that could be translated as "highest nirvana or liberation." Even though this term is found in some dictionaries, according to David Reigle this "is a ghost word, a word that appeared in a dictionary and was copied in other dictionaries, but has not been found in use in Sanskrit texts."
Mahatma Letter No. 18 in the chronological edition (or No. 9 in the three previous editions) presents the unknown term "Nirira namastaka."
Paraphrasing what is said in that letter, the Encyclopedic Theosophical Glossary defines this compound word as follows:
Nirira Namastaka: The ability of a high adept to produce from within his focus of consciousness or to exteriorize from it a substitute on a lower plane, which thereafter functions in all respects as would the full inner spiritual person were he present in the vehicle in which the substitute is acting. It is the same power but on a higher plane which enables the adept to transfer his mayavi-rupa to different parts of the earth, and to act in it; a power which in Tibetan is called hpho-wa.
Researching this term, Daniel Caldwell found that Nirira namastaka was a mistranscription of the original Letter. The correct transcription would be: "Nirvva namastaka." Searching now for this term he found a reference to the compound word Nirvvānamastaka in the 1869 edition of The New American Cyclopaedia, which explains:
. . .
or freedom from transmigration. Its etyma are:
nir, not; van, to blow, and arrow; its ortho-
graphy is Nirvvāna; its collaterals are: Nirvvā-
namastaka, liberation; nirvvāpa, putting out,
as a fire, &c. It is Nibbāna in Pali, Niban in
Burmese, Niruphan in Siamese, Ni-pan in Chi-
(The text above preserves the paragraph format on the original page.)
It seems clear that the term Nirvāṇamastaka is the one meant in the Mahatma Letter, and the source for the reference was The New American Cyclopaedia.
- A Mahatma Letters Puzzle by David Reigle