Two Wordlady fans have coincidentally written with questions about -or and -er endings.
-er vs -or: why are visitors and fighters spelled with different endings. Is there a rule?
In received spelling, the choice between the two forms [-er and -or] is often
capricious, or determined by other than historical reasons. Thus we have some Norman French agent nouns originally ending in -our which evolved into -er endings, among them:
interpreter came from interpretour < late Latin interpretātōr and was "interpretor" until the late 1500s when it became "interpreter".
barber (such a good word!) started off as Anglo-Norman barbour, from Old French barbeor < Latin barbātōr, and should have become "barbor", but evolved into "barber" by the end of the 1500s. The older form survives in the (especially Scottish) surname Barbour.
And then there were many nouns that had -er or -ier endings in Middle French, for instance
treasurer, gardener, customer, and many others.
And with many other words the -er ending just won out in English, despite the root verb being Latin.
The opposite also happened, though less frequently.
"Sailor" is derived from an Anglo-Saxon verb and was in fact originally "sailer", but "sailor" took over at the beginning of the 19th century. This was partly on the analogy of "tailor", which originally was Latin tāliātōr, and partly to make a distinction between professional sailors and amateur sailers. Nowadays, "sailer" only survives as a description of a kind of boat: A fast sailer such as Constitution could make as much as 14 knots under sail.
When did “advisor” become “adviser”? It seemed to occur overnight and no one told me when the vote was.
There's a difference between a financial adviser and a financial advisor: "Advisers" are regulated and have a legal responsibility to act in your best interest. "Advisors" are … not the same.
So, be careful: Banks may call them "advisors" so a salesperson sounds impressive, but you could be stuck without protection.
The Ontario Securities Commission confirms that "adviser" is a legal term under securities law that describes a person or company that is registered to give advice about securities, whereas "advisor" is not.This seems to me ridiculous, because we are just talking about a spelling variant. It's like saying that a labour negotiator doesn't have the same standing if you call them a labor negotiator instead.
(*Yet another one of those noun-verb conversions that we don't bat an eye at.)