Ylimegirl said:
Referring to the little bit of definition between her bikini bottom and her navel, yknow the naturally non-flat stomach had by woman in the real world (yes even skinny women) but rarely highlighted in illustrations. So above where the mons is.
pool #3683 exists for more intentional/exaggerated/noticeable examples, but I'm fairly sure there isn't currently any tag or place for when the fat there is defined but not a major feature of the image. The proper name (amidst a sea of colloquialisms with no prime standout) seems to be panniculus, if you wanted to start a tag for it.