synaptic knob
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synaptic knob
orbouton
one ofup to 50 swellings at the terminal branches of a neuron which, together with the area of invaginated muscular membrane beneath each, collectively form the endplate. see ENDPLATE, MOTOR.Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005