glib (adj.) Look up glib at Dictionary.com
1590s, "smooth and slippery," possibly a shortening of obsolete glibbery "slippery," which is perhaps from Low German glibberig "smooth, slippery," from Middle Low German glibberich, from or related to glibber "jelly." Of words, speakers, etc., from c.1600. Related: Glibly; glibness.