A stiffie is a slang term for a male’s erect penis. A stiffy occurs when the penis fills with blood, making it hard or stiff. This usually occurs because a male is physically or mentally aroused. A stiffie may also be called a boner or a hard on. Stiffie may also be spelled stiffy.
More About Stiffie
Most commonly a male will get a stiffie because he sees someone or something he finds sexually arousing. This stiffie makes it possible for the man to engage in sexual intercourse if he gets the opportunity. However, men also get stiffies for other reasons including feeling scared or feeling the intense need to urinate. Males also get stiffies while they sleep, although scientists aren’t sure why.
A stiffie stands straight up, creating a bulge in a man’s underpants and even his shorts or trousers. This can be embarrassing if it occurs at inopportune moments, especially for teenage boys who often have little control over the frequency of their stiffies.