What's the difference between "adviser" and "advisor"?

Since the root verb ("advise") ends in the letter E, I believe the -er suffix is preferred to the -or suffix. An analogous case is the verb organize, which becomes organizer (and clearly not "organizor").

That said, many dictionaries recognize "advisor" as an acceptable spelling of the word, and its usage seems to be pretty common.

English is odd and evolving (often not in an elegant way- particularly given the IM shortcuts and creative spelling habits of many); councilor, counselor, counsellor for example. I have a 17 yr old pen pal who sends me regular memes or blogspeak to torment me.

An “adviser” is one who offers and has given advice in the past, but is not presently giving it; while an “advisor” is one who is presently giving advice. Therefore, an advisee is the party accepting or receiving the advice presently.

Flukerr; Sorry but you are incorrect. The two words are now interchangeable and mean someone who gives advice. “Advisor” may be considered a more formal advice-giver. Advisee receives advice from either the adviser or the advisor.

An adviser is one who informally gives advice. This could be a good friend, a lawyer, and grandfather, etc. Their job isn’t specifically to give you advice, but they have acted in that capacity. If you are describing someone who has informally given you advice, you would say “Well, I made this decision because my adviser provided me with some new insight.” And advisor is one who is tasked with giving advice, usually on a formal level. This might mean an Academic Advisor at an educational institution. “The advisor instructed us to change our policy.” The reason a lawyer would fall into the “adviser” category, as opposed to the “advisor” category, is that a lawyer isn’t officially tasked with advising you, though you may have solicited this from them.

except, horsemencountry, you mix up the two -er and -or in your own example.