My personal definitions of shave quality (everyone's definition varies):
BBS (baby butt smooth) - Passes the cotton ball test. Feels perfectly smooth. I can rub a cotton ball across my head and no fibers will catch on stubble. A BBS must last me at least 8 hours for me to consider it a BBS. When my wife rubs her cheeks against it she says, “Mmmm, soft.”
DFS (damn fine shave) - The shave feels like BBS when I first finish but I can feel very light stubble, like a very fine sandpaper, in less than 8 hours. My hair usually grows into this category 9 - 12 hours after a successful BBS. I usually get a DFS with a razor I’m not used to yet or when I rush through my 3.5 pass shave. My wife says, "Mmmm, soft."
CCS (close, comfortable shave) - I can feel very light stubble, like a very fine sandpaper, immediately after finishing my shave. I usually get a CCS when I shave with disposable razors, a one pass shave where I can take my time on the one pass, or a normal 3.5 pass shave with a really crappy DE razor. I don’t necessarily consider it a comfortable shave. My wife says, "Don't kiss me again, you're giving me whisker burns".
SAS (socially acceptable shave) - I only use this definition for face shaves. You definitely will feel stubble over 100% of your face with a SAS. Up to 24 hours growth or a shave using a disposable razor with nothing but the very bare minimum (think just cold water and/or hand soap). This is shaving because you're required to shave and in an environment where you only have a razor and hopefully some form of lubricant. This is a shave done out of a canteen cup in the woods that takes off enough whiskers your 1SG, PSG or peers won’t call you out on it and high enough quality to lead by example and motivate your Soldiers to keep up on their shaves. A very hurried one pass shave. In the field or camping I let the hair on my head grow and actually have people buzz it with clippers if it gets too long. My wife says, "Why did I bother kicking my boyfriend out before you came home."
ATG (Against the grain shaving) - Shaving against the grain of your hair. It would be in the direction opposite of how your hair naturally lays or grows.
DSC (Dollar Shave Club)
KTG (Kitty-corner the grain shaving) - I believe I made this one up. Shaving at a 45 degree angle from the direction your hair naturally lays or grows. I go either against or with the grain based on where it's located on my head.
NOS (New Old Stock) - Refers to merchandise being offered for sale which was manufactured long ago but that has never been sold at retail. Such merchandise may not be produced anymore, and the new old stock may represent the only current market source of a particular item.
WTG (With the grain shaving) - Shaving with the grain of your hair. It would be with the direction your hair naturally lays or grows.
XTG (Across the grain shaving) - Shaving across the grain of your hair. It would be at a 90 degree angle from the direction your hair naturally lays or grows.