Jargon

Heard a couple new-to-me expressions this weekend. We were talking about why a radiologist might be needed at 2AM, and we were thinking, well, trauma in the Emergency Room. But then dutiful daughter mentions:

Decompensation - In medicine, decompensation is the functional deterioration of a structure or system that had been previously working with the help of compensation.

I suspect in everyday conversation you would call it 'taking a turn for the worse'. And yeah, if someone decompensated in the middle of the night, you might very well need a radiologist.

The other one I heard from a friend at happy hour:

Index of Refraction and Coefficient of Extinction are the real and complex portions of light.

Okay, there's a lot crammed into that sentence. I've heard of Index of Refraction, it just tells you how much light is bent, but Coefficient of Extinction is new to me. Wikipedia gives us this:

Extinction coefficient refers to several different measures of the absorption of light in a medium:

• Attenuation coefficient, sometimes called "extinction coefficient" in meteorology or climatology
• Mass extinction coefficient, how strongly a substance absorbs light at a given wavelength, per mass density
• Molar extinction coefficient, how strongly a substance absorbs light at a given wavelength, per molar concentration
• Optical extinction coefficient, the imaginary part of the complex index of refraction

I think the last one, Optical, is what we want, though what you would use it for is beyond me.