- -oid suffix for "like, like that of, thing like a ______," from Latinized form of Gk. -oeides, from eidos "form," related to idein "to see," eidenai "to know;" lit. "to see," from PIE *weid-es-, from root *weid- "to see, to know" (see VISION (Cf. vision)). The -o- is connective or a stem vowel from the previous element.
Etymology dictionary. 2014.