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Biannual vs. biennial

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January 10, 2003, 21:57
Biannual vs. biennial
In a meeting today, one of our board members discussed having a conference every two years. She kept calling it a biannual conference, while I thought to myself, "she really means biennial." Then I looked it up in my AHD and on dictionary.com. My dictionary only gave the definition of "twice yearly" or "semi-annually". However, some of the sites on dictionary.com said either twice yearly or every two years. Now--that isn't very precise is it? How do you use them?

By the way, this board member said, "Irregardless of whether we do the conference annually or biannually....." Grrrr! Mad
January 10, 2003, 22:19
Kalleh, you are right! The online dictionaries are very confusing. So I pulled out my "trusty, never dusty, Webster's" which states:

biannual ~ Occurring twice a year; semiannual.

biennial ~ Occuring every second year.

So, there you have it! She was wrong, and you were right! And you can tell her I said so! Razz
January 11, 2003, 01:39
The prefix bi- is problematic since in some words it means “occurring twice in a specified period of time” while in others in means “occurring once in two periods. In other words it can have either meaning (bimonthly, 1: occurring every two months or 2: occurring twice a month : SEMIMONTHLY; biweekly, 1 : occurring twice a week or 2: occurring every two weeks : FORTNIGHTLY - M-W)

Bill Bryson, in his excellent book, Bryson’s Dictionary of Troublesome Words (Broadway Books, 2002, previously published as Penguin Dictionary of Troublesome Words and Phrases by Penguin UK) says:

Bimonthly, biweekly. and similar designations are almost always ambiguous. It is far better to say ‘every two months,’ ‘twice a month,’ etc., as appropriate.”

January 11, 2003, 09:25
I wonder if the word purists would even find a distinction with semi-annual versus biannual. After all "semi" means half so semi-annual should mean every 6 months. Yet, biannual really only means twice a year. For example, I visit my dentist semi-annually (each July and December), but biannually I am in touch with my friend who lives in France. The latter example may refer to visits in June and August.
October 19, 2004, 18:23
revising a thread...

In a recent QT column, someone asked about the "biweekly" definition because of Dictionary.com. We have talked about "biannual" before. QT, with authority, said, "'Biweekly' is every two weeks. 'Semiweekly' is twice a week."

I don't think he is correct in that. In fact, I think more people say "biweekly" to mean twice a week than every two weeks. What would you say? I am thinking of e-mailing him about our thoughts.
October 19, 2004, 21:38
Usage Note: Bimonthly and
mean “once every two months” and “once every two weeks.” For “twice a month” and “twice a week,” the words semimonthly and semiweekly should be used. Since there is a great deal of confusion over the distinction, a writer is well advised to substitute expressions like
every two months
or twice a month where possible. However, each noun form has only one sense in the publishing world. Thus, a bimonthly is published every two months, and a biweekly every two weeks.

Source: The American Heritage® Dictionary of the English Language, Fourth Edition

Of course, you could go British on us and use fortnightly.

October 20, 2004, 18:56
Interesting that you should mention "fortnightly," Tinman. I have been reading a lot of research reports lately, as I am preparing a systematic review. Many of these are from England. The last one I read talked about meeting "fortnightly" with the subjects, for a total of 15 meetings in a year. Roll Eyes
October 21, 2004, 04:54
" meeting "fortnightly" with the subjects, for a total of 15 meetings in a year"

huh? How often is that, then? I'm confused!

"Happiness is not something ready made. It comes from your own actions.
~Dalai Lama
October 21, 2004, 05:59
They don't meet the other 22 weeks? It's an intercaldendary period, I guess. Wink
October 21, 2004, 10:42
Presumably this is some college research. Dunno about over there, but college vacations here would leave only about 30 weeks available for working.

Build a man a fire and he's warm for a day. Set a man on fire and he's warm for the rest of his life.
October 21, 2004, 19:48
Oh, I am so embarrassed. Red Face I checked again, and arnie is right. They had said "academic calendar year." Sorry!