glib
\ glib \ , adjective;
1.readily fluent, often thoughtlessly, superficially, or insincerely so: a glib talker; glib answers .
2.easy or unconstrained, as actions or manners.
3.Archaic . agile; spry.
Quotes:
"Maybe I was being glib about my annoyance." " Glib ? So you've been feeling glib lately. Insincere? Offhanded?"
-- David Gilbert, "The Normals: A Novel", 2004
“You're glib ,” she said as she clinked her glass to mine. “So am I.”
-- Otto Penzler, "Dangerous Women", 2005
Origin:
Glib is a shortening of a now-obsolete word glibbery , which meant "slippery."
Dictionary.com
