There are a number of synonyms for the phrase "in terminabilities," which refers to the concept of something being endless or countless in nature. Some similar phrases might include "infiniteness," "boundlessness," or "eternality." Other possible synonyms might include "permanence," "unlimitation," or "unboundedness," all of which convey a similar sense of something without clear boundaries or endpoints. This type of language can be useful when discussing abstract or philosophical concepts, as well as when trying to describe the infinite scope of certain scientific or mathematical phenomena. Overall, there are many ways to express the idea of "in terminability," and each one can offer a unique shade of meaning and nuance to help convey this complex and intriguing concept.