solar plex ‧ us /ˌsəʊlə ˈpleksəs $ ˌsoʊlər-/ BrE AmE noun [singular]
[ Date: 1700-1800 ; Origin: Because its nerves spread out from the center like the rays of the sun ]
the front part of your body just below your ↑ rib s :
a blow to the solar plexus