The word "antisense" refers to a molecule or gene that works in the opposite direction to another molecule or gene in the body. It is like a mirror image, where it does the opposite of what the original molecule or gene does. Full definition
Walton et al. «Prediction of Antisense Oligonucleotide Binding Affinity to A Structured RNA Target», Biotechnology and Bioengineering, 65 (1): 1 - 9, 1999. (lens.org)
Part of Hardy's excitement stems from the recent success of antisense drugs in spinal muscular atrophy (SMA), an inherited neuromuscular disorder in children. (scientificamerican.com)
Mice treated with antisense RNA (bottom) produced more dystrophin — colored red in this image — than did control mice (top). (sciencemag.org)