Adscititious comes from a very "knowledgeable" family-it ultimately derives from scire, the Latin verb meaning "to know." Scire also gave us science,conscience,prescience ("foreknowledge"), and nescience ("lack of knowledge"). Adscititious itself comes to us from scire by way of the Latin verb adsciscere, which means "to admit" or "to adopt." This explains why adscititious describes something adopted from an outside source.
borrowed from New Latin adscītīcius, ascītīcius, from Latin adscītus, ascītus, past participle of adscīscere, ascīscere "to take to oneself, admit, adopt" (from ad-ad- + scīscere "to get to know, ascertain, vote for, approve," inchoative derivative of scīre "to know") + -īcius-itious — more at science