{{TOC_Right}} '''Oct''' or '''OCT''' may refer to:
== Biology and medicine == * Optical coherence tomography, an imaging method * Organic cation transport protein, a type of protein * Optimal cutting temperature compound, used in histology * Oncology clinical trial, a clinical trial in cancer research * Oxytocin challenge test, a type of contraction stress test in late stage pregnancy * Obsessive compulsive tendencies, a criterion involved in the diagnosis of obsessive-compulsive disorder
== Mathematics == * Octal, abbreviated oct, the base-8 number system * Octahedron, sometimes abbreviated oct, a regular polyhedron * Odd cycle transversal, a concept in graph theory
== Science and technology == * Octave, symbol: oct., a unit of measurement in electronics * Octans, abbreviation: Oct, a constellation * Office of the Chief Technologist, a manager at the NASA Institute for Advanced Concepts * Optical coherence tomography, an imaging method * Olefin conversion technology, a method in industrial chemistry * Office Customisation Tool, available in some versions of Microsoft Office 2007
== Chinese places and companies == * Overseas Chinese Town, (narrowly) a theme park or (broadly) an area in Shenzhen ** OCT Tower, a skyscraper in Overseas Chinese Town ** Overseas Chinese Town station (OCT Station), a metro station in Shenzhen * Overseas Chinese Town Limited, a company *OCT Harbour, a retail development in Shenzhen
== Other uses == * Oct., an abbreviation for the month of October, the tenth month of the year * Ontario College of Teachers, a professional self-regulatory body ** Ontario Certified Teacher, a professional designation from the Ontario College of Teachers * Orangi Charitable Trust, a Pakistani microfinance organisation * Orion correlation theory, a fringe theory in Egyptology * Overseas countries and territories, special territories in relation to the European Union * Oxford Classical Texts, a book series * Oklahoma City Thunder, an American basketball team * Octuple scull, an eight-man racing shell found in the sport of rowing
== See also == *{{look from|Oct}} *{{look from|OCT}} *{{intitle|Oct}} * OTC (disambiguation)
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