What the hell, English:
| Word | Every Other X | Twice Every X |
| Biweekly (www.merriam-webster.com) | X | X |
| Semiweekly (www.merriam-webster.com) | X | |
| Bimonthly (www.merriam-webster.com) | X | X |
| Semimonthly (www.merriam-webster.com) | X | |
| Biannual (www.merriam-webster.com) | X | ? |
| Biennial (www.merriam-webster.com) | X | |
| Semiannual (www.merriam-webster.com) | X |
