Āyanā (feminine) [?] at As 259 and Vism 26 is a grammarian's construction, abstracted from feminine abstract words ending in °āyanā, e.g. kaṅkhā < kaṅkhāyanā, of which the correct explanation is a derivation from causative formation kaṅkhāyati > kaṅkhāy + a + nā. What the idea of Buddhaghosa was in propounding his explanation is hard to say, perhaps he related it to √i and understood it to be the same as āyāna.