Fall 1947: brilliance
(according to Augustus John, quoting a letter from Crowley in Chiaroscuro, Jonathan Cape, 1952, p. 82):
…
27 September, 1947…
The greetings of the Equinox of Autumn!
The Word of the Equinox is brilliance. [with “iance” in italics]. (Ring settled on the last five letters.) AL. 1 64.