The phrase "numerical superiority" means having more people or things on one side compared to the other. It refers to a situation where one group has a greater number or quantity than their opponent. Full definition
Part of the point of zombies is their overwhelming numerical superiority. (quartertothree.com)
Given that the Flying donkey's lined up in a 4 -4-2 on goal kicks, they obtained numerical superiority in the center of the pitch. (chiesaditotti.com)
The Colombian has gone beyond the typical «go to» man out wide whose sole job seemed to limited to creating numerical superiority with his extraordinary ability to get passed opponents in one - on - one situations. (italianfootballdaily.com)