Definition of "singlet"

A set of one, an item not part of a larger set, particularly

1. (physics) A multiplet having a single member, especially a single spectroscopic peak.  examples

2. (physics, quantum mechanics) A quantum state having zero spin.  quotations  examples

   Quotations

   • When a ground state molecule absorbs a photon, the values of the electron spins are not altered and thus the primary excited state is the singlet state.

     2003, Timothy M. Cox, 90: Protoporphyria, Karl M. Kadish, Kevin M. Smith, Roger Guilard, (editors), The Porphyrin Handbook, Volume 14: Medical Aspects of Porphyrins, page 132

   • However, even if it were possible to supply benzophenone with radiation of the appropriate wavelength to produce the second excited singlet state of the molecule, this singlet would rapidly convert to the lowest singlet state (S1).

     2010, Donald L. Pavia, Gary M. Lampman, George S. Kriz, Randall G. Engel, A Small Scale Approach to Organic Laboratory Techniques, page 416

3. (psychology, informal) A person who does not have a form of multiplicity, i.e. a single persona occupying one human body.  quotations

   Quotations

   • Singlet and monocultural identity is so normalized that many voice hearers and plurals don’t share their experiences with anyone, living in isolation (and sometimes in poverty) and spending considerable inner resources to manage postures and performances of ‘mental health’.

     2016, Lori F. Clarke, “Embracing Polyphony: Voices, Improvisation, and the Hearing Voices Network”, in Intersectionalities: A Global Journal of 2016 Social Work Analysis, Research, Polity, and Practice, volume 5, number 2, page 6

   • Her system started when she was 17 years old: “We were not created by trauma. It started from being a singlet (one body, one person), but then, we lost our sense of self. […]

     2017, Gergő Ribáry, László Lajtai, Zsolt Demetrovics, Aniko Maraz, “Multiplicity: An Explorative Interview Study on Personal Experiences of People with Multiple Selves”, in Frontiers in Psychology

   • More strongly, respect might require that singlets themselves accept, in the context of interacting with plurals, that people are truly distinct people.

     2020, Elizabeth Schechter, “What we can learn about respect and identity from plurals”, in JPCA Mag, number 1, page 38

A single piece of clothing, particularly

1. (UK, Australia, Ireland, Nigeria, New Zealand, Singapore) A sleeveless buttonless shirt with a low-cut neck.  quotations  examples

   Quotations

   • Winston wrenched his body out of bed — naked, for a member of the Outer Party received only 3,000 clothing coupons annually, and a suit of pyjamas was 600 — and seized a dingy singlet and a pair of shorts that were lying across a chair.

     1949, George Orwell, Nineteen Eighty-Four, page 28

   • The semiotics of the singlet - immediately identifiable in Australia, especially in its usual shade of blue, with male manual labourers16 - underlines the contrast between the effete fakery of ballroom costumes and real masculinity to be found underneath or in the world of folk dancing.

     2000, Nicole Matthews, Kitsch on the Fringe: Suburbia in Recent Australian Comedy Film, Roger Webster, Expanding Suburbia: Reviewing Suburban Narratives, page 176

   • However, even in the latter he wears a blue singlet to help remind the audience of his working-class roots.

     2006, Albert Moran, Errol Vieth, Film in Australia: An Introduction, page 85

   • Women wear dresses, cropped trousers and vests with lightweight linen jackets and you will find men in anything from a business suit to a pair of stubbies (very short shorts) and a singlet top (white vest) or knee-length cargo trousers.

     2009, Deborah Penrith, Live & Work in: Australia, Crimson Publishing, UK, page 192

2. (sports) A one-piece, tight-fitting uniform, usually made of spandex or nylon, required in wrestling and powerlifting.  examples