glib

Short definition from Wiktionary

Adjective

1. 1
   Having a ready flow of words but lacking thought or understanding; superficial; shallow.
2. 2
   Smooth or slippery.
3. 3
   Artfully persuasive but insincere in nature; smooth-talking, honey-tongued, silver-tongued.
4. 4
   Snarky or unserious in a disrespectful way.

Verb

1. 1
   To make smooth or slippery.
2. 2
   To castrate; to geld; to emasculate.

Noun

1. 1
   A person's mouth or tongue.
2. 2
   A mass of matted hair worn down over the eyes, formerly common in Ireland.