Yes, peak operating pressure, which hasn't dropped all that much by the time the bullet clears the muzzle gap on a revolver.
"9mm has a high peak pressure because it has to do what something like .38 does with a much smaller case."
The 9mm does NOT do what the .38 Special does.
The ballistics are NOT similar.
9mm ballistics are far closer to .357 Magnum ballistics.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.