The Collaborative International Dictionary
Excitatory \Ex*cit"a*to*ry\, a. [Cf. F. excitatoire.] Tending to excite; containing excitement; excitative.
Wiktionary
a. stimulating, exciting or causing excitation; excitative
WordNet
adj. (of drugs e.g.) able to excite or stimulate [syn: excitant, excitative]
Usage examples of "excitatory".
Since, in practice, neurons that input into a neuron must have either inhibitory or excitatory connections, each musicality neuron must have a fixed division of its inputs into those expected to be active and those expected to be inactive, and the musicality neuron will only be activated when the actual activity of the neurons that it receives input from takes on this pattern.
It was soon apparent that the vital molecule was the transmitter amino acid, glutamate, well known as one of the commonest of the excitatory neurotransmitters of the brain and present in high concentration within neurons.