Значения термина flat midriff на английском

Her most recent Instagram post was a photograph of herself baring her flat midriff three days ago.

It always works for Bogie in the old movies, but Katie got up, brushing nonexistent lint from the entrancingly flat midriff of her top.

Britney Spears prances down a brightly lit corridor, shirt tied above her pancake- flat midriff, leading her classmates in a display of wholesome, high-kicking, let's-do-the-show-right-here pizzazz.