English

Alternative forms

• semi-hourly

Adjective

semihourly ‎(not comparable)

1. (properly) Half-hourly: occurring every thirty minutes.

   The warship rang its semihourly bell, announcing it was now half past 10 o'clock.

2. (inexact) Roughly (but not exactly) hourly: occurring around every sixty minutes.

Adverb

semihourly ‎(not comparable)

1. (properly) Half-hourly: at intervals of 30 minutes.

   Samples were collected semihourly (on the hour and half hour) throughout the study.

2. (inexact) Roughly (but not exactly) hourly: at intervals of around 60 minutes.