'semiyearly' definitions:
- annual,
- biannual,
- biennial,
- bimonthly,
- biweekly,
- catamenial,
- centenary,
- centennial,
- daily,
- decennial,
- diurnal,
- fortnightly,
- hebdomadal,
- hourly,
- menstrual,
- momentary,
- momently,
- monthly,
- quarterly,
- quotidian,
- secular,
- semestral,
- semiannual,
- semimonthly,
- semiweekly,
- tertian,
- triennial,
- weekly,
- yearly
