Is There a Difference between "Bi" and "Semi"?
A prince was about to purchase a castle high on a rocky promontory, the perfect place to defend against marauding Visigoths. His princess loved the place because of the stunning view and the intriguing array of torture devices displayed in the dungeon. As the prince was about to sign the contract to purchase, he noticed the term bimonthly payments. Wait! Hold everything! What does that mean?
This is the only question on grammar that sends all of my references into a tailspin.
The editors of Merriam-Webster’s Concise Dictionary of English Usage write, “The typical letter writer [to the dictionary staff] is outraged or distressed that bimonthly, for example, may mean either ‘every two months’ or ‘twice a month.’” Big difference.
The Oxford American Dictionary defines biannual as “appearing or happening twice a year,” then notes: “‘Biannual’ and ‘biannually’ do not mean ‘every two years.’” Yet it defines bimonthly as “happening every second month” and also as “happening twice a month,” but warns that “careful writers” use semimonthly instead of bimonthly to mean “twice a month.” Semi is defined as “a prefix meaning half.”
Webster’s New Dictionary of Synonyms states, “The chief source of confusion is biannual, which is used to mean either twice a year or every two years.”
Theodore Bernstein in The Careful Writer holds, “Bimonthly means every two months, and nothing else.” But biweekly can mean “every two weeks,” or “twice a week.” He concludes, “Without question, man’s communication with his fellow man would be improved if semi- were used to mean half and bi- were reserved to mean two.”
Not one reference tries to explain how bi can mean “two” and semi can mean “half,” yet biannual and semiannual have somehow become synonymous. Here’s what I think happened: The prince buying the castle saw the term “bimonthly payments” and asked his lawyer and the seller’s lawyer if that meant “two monthly payments,” or “two-monthly payments?” and the lawyers said, “Yes!”
For realtors, bimonthly usually means “twice a month,” and biweekly means “every two weeks,” but buyers don’t know that and rightly assume that bimonthly can mean “once every two months.” Insurance brokers have to rely on HR people at client corporations to deduct insurance premiums from an employee’s wages, but the HR folks don’t know the difference between biweekly and semimonthly.
Hard Fast Rule: Never entrust to your readers the interpretation of any statement containing the prefix bi or semi coupled with “weekly,” “monthly,” or “annually.” What is in your head will not be in theirs. And lawyers, don’t try to define the words to mean whatever you want them to mean. Say it correctly in the first place. (See Tip: Alice in Law-Law-Land.) I understand how this started; I don’t understand why it has to continue. The confusion has led to millions of misunderstandings and thousands of lawsuits. So I propose:
first, we stop using bi or semi with “weekly,” “monthly,” “annual,” “annually,” “ennially,” or “centennial,” at all, ever. We don’t have to remove bi or semi from other words, because no one will ever confuse half a bicycle with two bicycles or half-conscious with twice as conscious.
second, we just write what we mean (what a concept), like: every other week, on Friday, for a total of 26 payments each year. Or: twice a month, on the 1st and the 15th, for a total of 24 payments each year. HR people will weep with gratitude; realtors will high-five; malpractice carriers will lower premiums; judges will smile; and various peoples of diverse origin and ethnicity will live in peace and harmony forever and ever. Amen.
third, we at least be consistent: semi always means “half”; bi always means “two.” So semiconscious would still refer to all teenagers (including the ones we used to be); “semiintelligent” would still describe those who are smart twice a week or once every two weeks (not a big difference); and “semiclassical” music would still include “Theme from The Apartment.” But:
bifurcate would mean two furcates;
Seminole would be half of a “nole,” as in Chief Osce;
bikini would be two kinies;
and seminary would be half of a nary.
That should solve the problem. If you’re onboard, let me know. And stay tuned for more Writing Tips from WordRake, coming your way every semifortnight.
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