It is often used in the phrase "well hung" or as part of a simile such as "hung like a horse."
More About Hung
Studies suggest that being hung matters much more for a heterosexual male than for a female partner. Research shows 85% of women are satisfied with the size of their partner’s penis, compared to just 55% of heterosexual men. Some women indicate a preference for hung men, but physically the vagina can accommodate large and small penises with the same relative degree of comfort. Before childbirth, a woman’s vagina is only around three inches long, and only an inch or so longer when she’s aroused.
For homosexual couples, a penis only needs to be 2.5 inches to hit the male G spot. The first centimeter or two inside the anus is also the most sensitive area. While many gay men show a preference for hung partners, many hung men report difficulties with topping due to their size. Despite this, studies show that men with large penises tend to be tops and men with smaller penises tend to bottom.