Eta (disambiguation)

Eta (Η, η) is the seventh letter of the Greek alphabet.

Eta or ETA or eTA may also refer to:

Organisations

• ETA (separatist group), Euskadi Ta Askatasuna, Basque separatist group
• Electronic Travel Authority (Australia)
• Electronic Travel Authorization (Canada)
• ETA – Empresa de Transporte Aéreo, a defunct Brazilian Airline
• ETA SA, a Swiss watchmaking company
• E-T-A, a German-based global manufacturer of circuit protection devices
• ETA Systems, defunct manufacturer of ETA10 supercomputers
• Electronics Technicians Association International
• Employment and Training Administration, a branch of the US Department of Labor
• Engineering and Technology Academy, San Antonio, Texas, US
• Environmental Transport Association, British roadside assistance company
• Ethiopian Teachers' Association
• Evangelical Theological Association, former teaching institute, Melbourne, Australia

Science and technology

• Eta meson, in particle physics, a strongly interacting boson
• Dedekind eta function, a complex function defined in the upper plane
• Dirichlet eta function, an entire complex function
• Eicosatetraenoic acid, an omega-3 fatty acid
• Ethanolamine, a weak base
• Event tree analysis, a logical modeling technique
• Hapticity, η
• Pseudorapidity, η, in experimental particle physics, a spatial coordinate describing the angle of a particle relative to the beam axis
• Viscosity, a measure of a fluid's resistance to deformation

Other uses

• Eta (given name), a feminine given name
• European Technical Assessment of the European Organisation for Technical Approvals for construction products
• Eta (glider), a German glider
• Eta, derogatory term for the Burakumin in the Japanese feudal era
• 'eta, a letter or glottal stop in the Tahitian languages
• Eta, a snack food brand owned by Griffin's Foods
• Estimated time of arrival, frequently abbreviated to ETA.

See also

• Eta conversion or η-conversion, the idea of extensionality in lambda calculus