A type of mammal that lays eggs instead of giving birth to live young.
The platypus and the echidna are the only known monotremes that exist in the world.
Just as true monotreme are strange misfit animals whose parts are an awkward fit like the platypus; a mammal that lays eggs, oozes milk out of chest area with no nipples and webbed feet and bill like a duck, in urban parlance a person with a strange body that doesn't seem to fit together right like thick legs and tiny upper body is a MONOTREME
"Dude, is a total monotreme he can't run or move right and has a funny body."