`
`From "Collins English Dictionary"
`
` Collins English Dictionary, © HarperCollins Publishers 2000
`
`noun plural -cuses or -ci
`1. a point of convergence of light or other electromagnetic radiation, particles, sound waves, etc., or a point
`from which they appear to diverge.
`2. another name for focal point (1), focal length.
`3. Optics the state of an optical image when it is distinct and clearly defined or the state of an instrument
`producing this image: the picture is in focus; the telescope is out of focus.
`4. a point upon which attention, activity, etc., is directed or concentrated.
`5. Geometry a fixed reference point on the concave side of a conic section, used when defining its
`eccentricity.
`6. the point beneath the earth's surface at which an earthquake or underground nuclear explosion
`originates. Compare epicentre.
`7. Pathol the main site of an infection or a localized region of diseased tissue.
`verb -cuses, -cusing, -cused or -cusses, -cussing, -cussed
`8. to bring or come to a focus or into focus.
`9. (tr; often followed by on) to fix attention (on); concentrate.
`
`[C17: via New Latin from Latin: hearth, fireplace].
`
`Derived words: focusable adjective, focuser noun.
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` Collins English Dictionary, © HarperCollins Publishers 2000
`
`Persistent URL to the Entry: http://search.credoreference.com/content/entry/hcengdict/focus/0
`
`APA
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`Focus. (2000). In Collins english dictionary. Retrieved from
`http://search.credoreference.com/content/entry/hcengdict/focus/0
`
`MLA
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`"Focus." Collins English Dictionary. London: Collins, 2000. Credo Reference. Web. 1 July 2014.
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`Chicago
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`"Focus." In Collins English Dictionary. London: Collins, 2000.
`http://search.credoreference.com/content/entry/hcengdict/focus/0 (accessed July 1, 2014.)
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`Harvard
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`2000 'Focus' in Collins english dictionary, Collins, London, United Kingdom. Accessed: 1 July 2014,
`from Credo Reference
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