Really, I just need the definition of a "gendered body" broken down into something a bit easier to understand
Gendered Body might
have to do with how the societal world around us shapes our perceptions of our physical bodies. This has a lot to do with bulk of the population being encouraged to participate in (usually heterosexual) gender identity conformity.
Human bodies are shaped and controlled by the norms and pathways of the gendered social orders. How you dress, your diet, manner of speech, to meet social expectations. American culture has moved slightly away from this, but only slightly. Little boys still get baseball gloves, and little girls get soft dolls.
It might help to know the title of the textbook, and it's author[s].