Singlet may refer to:
*
singlet state
In quantum mechanics, a singlet state usually refers to a system in which all electrons are paired. The term 'singlet' originally meant a linked set of particles whose net angular momentum is zero, that is, whose overall spin quantum number s=0. As ...
, in theoretical physics, a quantum state with zero spin
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Singlet fission, in molecular photophysics
* in spectroscopy, an entity appearing as a single peak; see
NMR spectroscopy
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. The sample is placed in a magnetic fiel ...
* in optics, a single lens element, the building blocks of lens systems; see
lens (optics)
A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements' ...
* a one-piece collarless garment, also known as a
sleeveless shirt
A sleeveless shirt is a shirt that is manufactured without sleeves or whose sleeves have been cut off. Depending on the style, they can be worn as undershirts, by athletes in sports such as track and field and triathlon, or as casual wear by ...
or
vest
A waistcoat ( UK and Commonwealth, or ; colloquially called a weskit), or vest ( US and Canada), is a sleeveless upper-body garment. It is usually worn over a dress shirt and necktie and below a coat as a part of most men's formal wea ...
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wrestling singlet
A wrestling singlet (or simply singlet) is a one-piece, tight-fitting, uniform, usually made of spandex/lycra, or nylon, used in amateur wrestling. The uniform is tight-fitting so as not to get grasped accidentally by one's opponent, and allows ...
, a one-piece garment specific to wrestling
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BID/60, a British encryption machine
*
Singlet oxygen
Singlet oxygen, systematically named dioxygen(singlet) and dioxidene, is a gaseous inorganic chemical with the formula O=O (also written as or ), which is in a quantum state where all electrons are spin paired. It is kinetically unstable at ambie ...
, the common name used for an excited form of molecular oxygen
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