What does OS stand for?

What does OS mean?

OS	On Sheet Business » Accounting
OS	Open Space Academic & Science » Architecture
OS	Orzya Sativa Academic & Science » Botany
OS	left eye–oculus sinister Medical » British Medicine
OS	mouth (os) Medical » British Medicine
OS	obese strain Medical » British Medicine
OS	observational study Medical » British Medicine
OS	occupational safety Medical » British Medicine
OS	office surgery Medical » British Medicine
OS	oligosaccharide Medical » British Medicine
OS	Omenn syndrome Medical » British Medicine
OS	opening snap Medical » British Medicine
OS	Opitz syndrome Medical » British Medicine
OS	oral solution Medical » British Medicine
OS	organ-specific Medical » British Medicine
OS	Osgood-Schlatter Medical » British Medicine
OS	osteosarcoma Medical » British Medicine
OS	osteosclerosis Medical » British Medicine
OS	outer segment Medical » British Medicine
OS	overlap syndrome Medical » British Medicine
OS	oxidative stress Medical » British Medicine
Os	Osmium Academic & Science » Chemistry
OS	One Size Miscellaneous » Clothes
OS	Over Sized Miscellaneous » Clothes
OS	Operating System Computing » Drivers