The Collaborative International Dictionary of English v.0.48:

Pablum \Pablum\ n.
   1. A form of cereal for infants. [Trademark]
      [WordNet 1.5]

   2. A diet that does not require chewing.

   Syn: soft diet, pap, spoon food.
        [WordNet 1.5]

   3. Worthless or oversimplified ideas.

   Syn: pap, pabulum[3].
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Pablum
    n 1: a soft form of cereal for infants
    2: worthless or oversimplified ideas [syn: pap, pablum]