atheistical

From atheist +‎ -ical.^[1] Attested earlier than atheistic.

atheistical (comparative more atheistical, superlative most atheistical)

1. Of or relating to atheism; atheistic.
   • 1827 July, “Asiatic Society of Calcutta”, in The Oriental Herald, and Journal of General Literature, volume XIV, number 43, London: Printed [by J. R. Gordon, 147, Strand] for the editor, and sold by all booksellers, →OCLC, page 147:

     A letter from Mr. [Brian Houghton] Hodgson to Mr. Bayley, was then read, giving an outline of the theocracy of the Buddha system of Nepal. […] According to the information now communicated, the northern Buddhas acknowledge four sets of divine beings, or of superhuman objects of veneration. The first of these is, contrary to the generally supposed atheistical tendency of the faith, one primæval and uncreated deity. This first Buddha manifested five of his attributes, as five secondary Buddhas; in one of whom, Amitabha, or the 'immeasurably splendid,' in Prakrit and Pali, Amitabo, we recognise the Amito of the Japanese.

• atheisticall (obsolete)

• atheistic

• theistical

• atheism
• atheist
• atheistically