Simple Definition of ratio

from our Learner's Dictionary

ratio

noun

plural ratios
: the relationship that exists between the size, number, or amount of two things and that is often represented by two numbers
The college has a 12:1 ratio between students and teachers. = The college's student-to-teacher ratio is 12 to 1. [=for every 12 students, there is one teacher]
What is the length-to-width ratio?
often + of
The ratio of students to teachers is 12 to 1.
Women outnumbered men by a ratio of three to two. [=for every three women, there were two men]
The office has a high ratio of males to females. [=there are many more males that work at the office than females]

Cite this Entry

“Ratio.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/ratio. Accessed 21 Jun. 2026.

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