Pronunciation: [dɪfˈə͡ʊkəs] (IPA) 
Defocus is a term used in photography and optometry to describe the blurring of an image. It is spelled as dɪˈfoʊkəs, with the emphasis on the second syllable. The "de" prefix means "away from" or "not," while "focus" refers to the clearness or sharpness of an image. The "f" and "c" sounds reflect the Latin origins of the word, as the letter "f" was used instead of "ph" in the original spelling, and the "c" was pronounced like "k."
Defocus is a verb that describes the action of intentionally causing something, usually an image or object, to appear blurred or out of focus. When an object is defocused, its details become less distinct and its edges may appear unclear or fuzzy. This effect is commonly achieved by adjusting the focus of a camera lens or, in some cases, by manipulating an object or subject itself.
In the context of photography or cinematography, defocusing is often used to create artistic or aesthetic effects. By deliberately blurring certain areas or the entirety of an image, photographers and filmmakers can convey a sense of dreaminess, abstraction, or emotional impact. This technique can draw attention to specific elements within the frame or evoke a sense of depth and atmosphere.
Defocus can also refer to a deliberate act of intentionally diverting or shifting focus away from a particular subject or topic. For example, in a conversation or presentation, an individual may choose to defocus on a sensitive issue by shifting the discussion towards another subject that is seen as less controversial or more comfortable for the participants involved.
Overall, the concept of defocus encompasses both the physical act of manipulating focus in visual media and the intentional shift of attention away from a specific subject.
The word "defocus" is formed by adding the prefix "de-" to the word "focus". The prefix "de-" comes from Latin, meaning "from" or "remove". "Focus" itself has its roots in Latin where it referred to a fireplace or hearth. Over time, it came to represent the point of convergence of rays of light or the center of attention. Thus, "defocus" appropriately suggests removing or diverting attention or blurring the point of convergence.
