The bulk update request #10120 has been approved by @nonamethanks.
create alias thin_waist -> narrow_waist
create alias slim_waist -> narrow_waist
create alias large_hips -> wide_hips
Slender waist was aliased to narrow waist in topic #18904 so I see these being valid as well, I can't always remember the word narrow, as for large hips, there isn't much to say.