Hemisphere/ˈhemɪsfɪr/ Definition 1 of 4Pro Tip 1/2Visual Imagery Imagine cutting a ball in half; each part is similar to a hemisphere. When you cut a melon in two, you create two hemispheres. Pro Tip 2/2Not Literal Sometimes 'hemisphere' describes areas or aspects, not always physical halves. The chef divided his menu into hemispheres of flavor.