(of motives, etcetera) unstated; beyond what is explicitly said
I soon realized that he had had an ulterior motive in seeking my friendship: namely, the desire to have easier access to my sister, with whom he was secretly in love.
ulterior (more distant, more remote, farther, on the farther side) (Latin)
ulterior = ultra + interior which is very much inside means hidden. relate it to exterior which means remote or outside, and has the same meaning as ulterior. ulterior. sounds liks ul - terror seems me to be A terririst group called 'UL' zazira terririst grp. which are intentionally hidden somewhere in kashmir