NOUN (3)

1. the condition of being made easy (or easier);
- Example: "social facilitation is an adaptive condition"

2. (neurophysiology) phenomenon that occurs when two or more neural impulses that alone are not enough to trigger a response in a neuron combine to trigger an action potential;

3. act of assisting or making easier the progress or improvement of something;

The Collaborative International Dictionary of English v.0.48:

Facilitation \Fa*cil`i*ta"tion\, n.
   The act of facilitating or making easy.
   [1913 Webster]

WordNet (r) 3.0 (2006):

facilitation
    n 1: the condition of being made easy (or easier); "social
         facilitation is an adaptive condition"
    2: (neurophysiology) phenomenon that occurs when two or more
       neural impulses that alone are not enough to trigger a
       response in a neuron combine to trigger an action potential
    3: act of assisting or making easier the progress or improvement
       of something