What they've said (and some of the words were put in a category by more than one person, but here's how they spread among the categories):
Very positive: lean, slender, delicate, svelte, slim, skinny
Positive: Thin, delicate, svelte
Negative: lanky, gangling, bony
Very negative: Rawboned, cadaverous, emaciated, underfed, skeletal, fleshless, spindly, haggard, undernourished
When the professor claimed that the overweight words were generally less offensive than the underweight words, there was an outcry from most of the women in the class. Many of the men asserted that “stocky,” “bulky,” or “beefy” were positive. No women agreed. Several of the women said that they’d rather be called “underweight” than “well-fed” or “chubby.”
There were also differences in terms of to whom the adjectives were applied:
-“delicate” was better perceived when discussing a woman
-“lanky” better perceived when discussing a man
-“plump” was an interesting case – men said that it was only good when applied to a woman, and women said it was only good when applied to a man! “Plump” was eventually deemed only appropriate when discussing one’s parents.
There were other age issues present in our discussion, namely that “lanky” or “gangly” could be a positive adjective when referring to a growing boy.
I personally think it would be interesting to poll my entire campus about this, including people's attitudes towards their own bodies...but then again, I'm not exactly a linguistics major, so I don't really have the expertise to analyze it.