What is the meaning of the suffix "ar"?

The suffix "ar" is a variant of "al," another adjective-forming suffix, and is from the Latin root "aris," meaning "of, near or pertaining to something." The suffix "ar" is used with words in which a lowercase "l" precedes the suffix, such as singular, lunar and circular.

The suffix "ar" also has Old French and Anglo-French roots, and it replaced the Middle English suffix "er." The suffix "ar" is also commonly used to form certain nouns, such as burglar, cellar, liar, scholar, mortar, poplar and vinegar. If a root word ends with "r," then the suffix "al" is often used. Both "al" and "ar" are used when turning the noun "line" into the adjectives "linear" and "lineal."