We show that the radial acceleration relation for rotationally-supported galaxies may be explained, in the absence of cold dark matter, by a non-minimally coupled scalar field, whose fifth forces are partially screened on galactic scales by the symmetron mechanism. In addition, we show that sufficient energy is stored in the symmetron field to explain the dynamic stability of galactic disks.

6 pages, 3 figures, revtex format; discussion of disk stability corrected, incorrect direct mass bound removed, conclusions unaltered; corrections submitted as an erratum to Physical Review D