- Adviser is a person who gives advice.
- An advisor does the same thing—the only difference is in the spelling.
- Adviser is the older and the preferred spelling.
Advisor vs. adviser is probably not the most important or the most annoying conundrum related to the verb advise. That honor goes to advise vs. advice because mixing them up is a more damaging mistake. But still, people wonder about advisor and adviser because we don’t have two different spellings for every word in the English language—it’s not common.