glibbest

/G L IH1 B IH0 S T/
adjective
  1. 1

    Having a ready flow of words but lacking thought or understanding; superficial; shallow.

  2. 2

    Smooth or slippery.

    โ€œa sheet of glib iceโ€

  3. 3

    Artfully persuasive but insincere in nature; smooth-talking, honey-tongued, silver-tongued.

    โ€œa glib tongue; a glib speechโ€

Source: https://en.wiktionary.org/wiki/glib, https://en.wiktionary.org/wiki/glibbest