Practical answer that aligns with common usage and not strictly dictionary usage:
Personally, I would use the term/phrase "Body glorification" (or "Body praising" as user46359 stated), as that more accurately represents the exact opposite connotation of "Body shaming" and is immediately clear that the connotation is not just positive, but is in fact exceedingly positive.
"Body positivity" is supposed to imply "all bodies are good" with a slightly positive connotation, including anorexic bodies, extremely muscular and low bodyfat bodies, average bodies, healthy bodies, small bodies, irregularly-shaped bodies, wrinkly bodies, bodies with missing limb(s)/finger(s)/jaw/mouth/nose/eye(s)/ear(s), hairy bodies, bodies with alopecia, bodies with a disproportionate ratio between body parts (such as torso-to-leg, facial width to facial height, etc), visually asymmetric bodies, and discolored bodies.
However, "Body positivity" is almost always used only in reference to morbidly obese people.
- "Toxic body positivity" (where Toxic describes Positivity, not Body) is sometimes used to call attention to the highly-specific emotional usage of the phrase "Body positivity" for morbidly obese people, though even that counter-phrase is more specific than it's intended to be.
- Some beauty-brand campaigns are trying to change this singular usage of Body positivity only describes morbidly obese people though, such as Dove [1] [2], even if they are still very strongly limiting the types of bodies they display due to 1) not having a significant-enough consumer base in the set of bodies they're choosing not to display (i.e., irrelevant "good" bodies) or 2) an unspoken/unacknowledged public disgust factor that would turn people away from buying their products upon seeing an ad featuring a "good" body that is, visually speaking, extremely displeasing to the general public.
If you ignore the face-value meaning of the phrase "Body positivity" implying a somewhat positive connotation to bodies, then "Body positivity" is the antonym for "Body shaming", at least with respect to common usage on social media.
In terms of connotation strength from weakest positive to strongest positive, I would rate the phrases as follows:
"Appearance hate/hatred" < "Body shaming" < "Body neutrality" (non-emotional, therefore no positive nor negative connotation) < "Self acceptance" (wrt bodies) < "Body appreciation" < "Body positivity" < "Body glorification" = "Body praising"
- Something noteworthy: "Body <insert descriptor here>" implies a focus on the body, which is typically interpreted as the physically largest part of the body (such as torso in most cases, or sometimes the legs) rather than the entire human body. Therefore, smaller but still very noticeable, regions like the face, arms, teeth, smile, hands, feet, etc can be described by "Body <insert descriptor here>", but there is no guarantee that that interpretation is common usage, just like how "Body positivity" technically means "all bodies are good" despite it not typically being used in that general manner.
