Presynaptic Neuron: A presynaptic neuron is the sending neuron in a synapse that releases neurotransmitters into the synaptic cleft.
Postsynaptic Neuron: A postsynaptic neuron is the receiving neuron in a synapse that contains receptors for binding with neurotransmitters released by presynaptic neurons.
Synaptic Cleft: The synaptic cleft is a small gap between the presynaptic and postsynaptic neurons where neurotransmitters are released and travel across to bind with receptors.