See inhibitory post-synaptic potential.
<abbreviation> Inhibitory postsynaptic potential. ... (05 Mar 2000) ... 
Type: Abbreviation Definitions: 1. Abbreviation for inhibitory postsynaptic potential.
Inhibitory postsynaptic potential; hyperpolarization of the postsynaptic membrane in response to a particular neurotransmitter chemical, which makes it more difficult for the postsynaptic cell to attain a threshold level of depolarization required to produce action potentials. It is responsible for postsynaptic inhibition.