Q: Is there any particular reason that “beggar” is spelled with an “-ar” suffix instead of an “-er” or an “-or”?
A: The word “beggar” used to be spelled with an “-er” suffix. That was the usual spelling for centuries after the word was first recorded in Middle English in the late 12th century.
The Oxford English Dictionary says, “the spelling in -ar has been occasional from 14th cent.,” but the “-er” suffix was still “the usual form in 15-17th cent., as an ordinary agent-noun.”
An agent noun, one denoting the performer of an action (like “painter” or “actor”), usually ends in “-er” or “-or,” but the suffix “-ar” may appear in words influenced by their Latin or French forms.
As the OED explains, English agent nouns with an “-ar” suffix generally “show a remodelling or replacement of an earlier form in -er from Old French -ier, either after Latin (compare e.g. bursar n., medlar n., or mortar n.1), or after a corresponding French form in –aire (compare e.g. vicar n. and vicary n.1).”
Interestingly, the earliest Oxford example for the usage doesn’t end in “-er,” “-ar,” or “-or.” In the citation, a beggares is a woman who begs:
“Hit is beggares rihte uorte beren bagge on bac” (“It is right [for the] beggaress to carry a bag on [her] back”). From Ancrene Riwle, an anonymous guide for monastic women, written sometime before 1200.
The dictionary’s next example ends in an “-ere” suffix: “Þu wenest I beo a beggere” (“You think I am a beggar”). From King Horn, an anonymous Middle English romance written sometime before 1300.
And here’s an “-er” example from the Wycliffe Bible of 1382: “nedi and begger there shal not be among ȝow” (“there shall not be a needy man or a beggar among you”). Deuteronomy 15:4.
The earliest OED citation with the modern spelling “beggar” appeared in the late 14th century: “And now me bus [I must], as a beggar, my bred for to thigge [beg].” From an anonymous Middle English translation, dated sometime before 1400, of the Italian writer Guido delle Colonna’s Latin Historia Destructionis Troiae.
Despite that early appearance of “beggar,” the old form “begger” continued to be seen for hundreds of years.
Oxford has this biblical example, which we’ve expanded, from the King James Version of 1611: “And there was a certaine begger named Lazarus, which was layde at his gate full of sores” (Luke 16:20).
And here’s an expanded OED citation from Shakespeare’s play The Tempest, believed written around the same time: “They will not giue a doit [a trivial sum] to relieue a lame Begger.” The reference is to an old Dutch copper coin, the duit.
Similar nouns ending in “-ar” today, besides “beggar,” “bursar,” and “vicar,” include “scholar,” “registrar,” “liar,” “burglar,” and “friar.”