-oid Look up -oid at Dictionary.com
word-forming element meaning "like, like that of, thing like a ______," from Latinized form of Greek -oeides, from eidos "form," related to idein "to see," eidenai "to know;" literally "to see," from PIE *weid-es-, from root *weid- "to see." The -o- is connective or a stem vowel from the previous element.