S-R connection n (Psychology) psychol stimulus-response connection; the basic unit of learning according to behaviourist learning theory. See also reflex arc Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014