dpi
UK[ˌdiːpiːˈaɪ]US[ˌdiːpiːˈaɪ]
n
A measure of the resolution of a printer, scanner, or monitor, expressed as the number of individual dots that can be placed in a line within the span of one inch.
Morpheme Breakdown
d
p
i
d
dot
p
per
i
inch
Etymology
The term DPI is a modern initialism, born from the technical jargon of the digital imaging and printing industries in the late 20th century. It is formed by combining the first letters of the English phrase "dots per inch," which literally describes its function as a linear measurement of spatial printing or display density. This compound abbreviation follows a common pattern in technical English for creating concise metrics, such as PPI (pixels per inch) or RPM (revolutions per minute). Its logic is purely descriptive and utilitarian, directly encoding the core concept of quantifying resolution by counting discrete units (dots) over a standardized physical distance (one inch).
Analysis
Structure: d (dot) + p (per) + i (inch)
d: An abbreviation for the English word "dot," representing the smallest discrete point in a digital image.
p: An abbreviation for the English preposition "per," indicating a rate or ratio.
i: An abbreviation for the English unit of length "inch."
Examples
For high-quality photo printing, an image resolution of 300 dpi is typically recommended.
This old scanner has a maximum optical resolution of only 600 dpi.
The difference between a 72 dpi screen image and a 300 dpi printed version is very noticeable.