A beta male would be the exact opposite of an Alpha male. First, notice that beta male isn't capitalized like Alpha male, and that is for a reason. beta males are plagued with anxiety, insecurity, and are all around dominated by their peers. beta males are unlikely to ever find success, mostly due to their lack of confidence and insufficient sexual demeanor.
Woman: "That beta male couldn't even keep his dick up for thirty seconds, I need an alpha that could keep it as hard as steel."