bantam weight
Definition
A weight class in combat sports (such as boxing, kickboxing, and MMA) consisting of athletes typically weighing between 115 and 135 pounds, depending on the specific sport and governing body.
A term used descriptively to refer to someone or something that is small but notably feisty, scrappy, or possessing a 'punch' that exceeds their physical size.
Examples
Despite being a bantam weight, my terrier managed to convince the mailman that the entire porch was a sovereign nation.
The accountant displayed bantam weight energy, fearlessly challenging the tax auditor over a discrepancy involving two paperclips and a staple.
Moving from the heavyweight division to bantam weight required him to stop eating everything that wasn't nailed down and start viewing salads as something other than a garnish.