raster
C1/C2Technical/Formal
Definition
Meaning
A rectangular grid of pixels or points that forms an image on a screen or is used to create an image in printing or display technology.
The method of constructing an image by scanning successive parallel lines (as in early television or certain printing technologies) or the resultant data structure representing a bitmap image in computing.
Linguistics
Semantic Notes
Primarily a technical term from computer graphics and imaging. The concept is fundamental to digital displays and printing, opposed to 'vector' graphics which use mathematical descriptions of lines and curves. Can refer to both the grid structure and the process of creating an image via scanning lines.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage; both varieties use the term identically in technical contexts.
Connotations
Neutral technical term in both varieties.
Frequency
Equally low-frequency in general discourse but standard in technical fields in both regions.
Vocabulary
Collocations
Grammar
Valency Patterns
[noun] + raster[adjective] + rasterraster + [noun]convert + [object] + to + rasterVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “[No common idioms for this technical term]”
Usage
Context Usage
Business
Used in discussions of graphic design, printing, and software capabilities (e.g., 'The logo needs to be provided as a raster file for the brochure.').
Academic
Common in computer science, graphic design, cartography, and remote sensing papers (e.g., 'The study compared raster and vector models for geographic data.').
Everyday
Very rare in casual conversation. Might be encountered by users of photo editing or design software.
Technical
The primary domain. Refers to the fundamental data structure for digital images, displays, and certain printing processes.
Examples
By Part of Speech
verb
British English
- The software will rasterise the vector artwork before printing.
- You need to raster the text layer to apply this filter.
American English
- The software will rasterize the vector artwork before printing.
- The program rastered the map for web display.
adverb
British English
- [Adverbial use is extremely rare and non-standard for this word.]
American English
- [Adverbial use is extremely rare and non-standard for this word.]
adjective
British English
- It's a raster image format, not a vector one.
- The old system used a raster display tube.
American English
- We need a raster graphic for the website banner.
- Raster data sets can be very large.
Examples
By CEFR Level
- [Too technical for A2 level. Not typically introduced.]
- [Too technical for B1 level. Not typically introduced.]
- The photograph is saved as a raster file, like a JPEG.
- Enlarging a raster image too much makes it look blurry.
- The GIS application allows users to overlay vector data on a raster base map.
- The printer driver converts all incoming data to a raster format for the print engine.
Learning
Memory Aids
Mnemonic
Think of a RASTER as a RAST of TElevision lines, or remember that a RASTER image is like a grid of tiny little ASTERisks (*).
Conceptual Metaphor
A DIGITAL CANVAS made of a fixed grid of tiny tiles (pixels).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid confusing with 'растр' (which is the direct equivalent) and 'растер' (which could be misheard as 'расстер' from 'растерять' - to lose). The technical term is directly borrowed as 'растр'.
Common Mistakes
- Mispronouncing it as 'racer' or 'raster' (with a long 'a').
- Using 'raster' to describe non-grid-based images.
- Confusing 'rasterize' (the verb) with 'raster' (the noun).
Practice
Quiz
What is the primary characteristic of a 'raster' image?
FAQ
Frequently Asked Questions
Raster graphics (like photos) are made of a fixed grid of pixels and become blurry when enlarged. Vector graphics (like logos) use mathematical paths and can be scaled to any size without losing quality.
JPEG is a raster file format. It contains data for a fixed grid of pixels, which is why photos saved as JPEGs lose quality if you zoom in too much.
To 'rasterize' means to convert an image (usually a vector graphic) into a raster or bitmap format, turning lines and shapes into a grid of pixels.
It comes from the German 'Raster', meaning 'screen' or 'grid', which itself derives from the Latin 'rastrum' meaning 'rake', referring to the series of parallel lines.