in terminables: (probably) in definite terms, definitely; cf. in terms (see termn. Phrases 1a). Obsolete. rare.
ΚΠ
a1568 For Helth of Body 70 in Bannatyne Poems (1896) 198 Woyd all drinking with lymmaris and lechouris, And this I say in terminablis, I gess, Off dyce playeris and commoun hasardouris.