Conjecture.
Part of speech: Noun, common, feminine
Inflection: Fi-o = Feminine i/o-stems [St §152.A6; BE §103.A1]
Streitberg 1910, p. 38 – text | facs.
[fraqisteins] Fi/o (1526) Verderb, Vergeudung: Konjektur GLs für . . . teins Mc 14,4 CA.