biweekly, bimonthly, biannual

(A similar topic is discussed in French in the article bihebdomadaire.)

Biweekly means either twice a week or every two weeks and can therefore create confusion for the reader. A similar problem occurs with bimonthly and biannually.

To ensure clarity, replace these ambiguous terms with the precise expressions “twice a week (or month or year)” or “every two weeks (or months or years).”

• The meetings occur twice a week / every two weeks. (not biweekly)
• We get paid twice a month / every two months. (not bimonthly)
• We attend a family reunion twice a year / every two years. (not biannually)

When the adjective biannual means “twice a year,” it can be replaced with semi-annual or twice-yearly; when it means “every two years,” it can be replaced with biennial.

• The semi-annual / twice-yearly (not biannual) reunion is always a favourite.

OR

• The biennial (not biannual) reunion is always a favourite.

Note that no hyphen is used after the prefix bi-.