"Flat stomach" - what does that mean to men? Abs, no abs? What is preferred?

When guys say they prefer a 'flat stomach', does that mean with ab/muscle definition and completely flat as a pancake, flat but no definition, or "generally" flat (as she doesn't have a huge potbelly)? If you could tell me which of these are the 'ideal' flat stomach or qualify as a flat stomach that would be helpful. Just trying to get a better picture of what this term means for men.

1.
flat stomach on girls
flat stomach on girls
2.
flat stomach woman
flat stomach woman
3.
is this flat stomach?
is this flat stomach?
4.
abs no abs?
abs no abs?
"Flat stomach" - what does that mean to men? Abs, no abs? What is preferred?
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