reading, 'riting, and 'rithmetic, regarded as the fundamentals of education.
2.
the fundamentals, basic knowledge, or skills of any system or field:
the three R's of good government.
Origin
1820-30
Related Abbreviations for three R's
three R's
reading, writing, and arithmetic
Idioms and Phrases with three R's
three R's
The fundamentals of education, as in It's a terrible school; the children are not even taught the three R's. It is widely believed that Sir William Curtis, an alderman who became Lord Mayor of London, once presented a toast to the three R's—reading, riting, and rithmetic—thereby betraying his illiteracy. In any event, the term was picked up by others and so used from the early 1800s on.