semihourly
Half-hourly: occurring every thirty minutesHalf-hourly: occurring every thirty minutes.
Meaning
2 senses(not comparable)Half-hourly: occurring every thirty minutes.
The warship rang its semihourly bell, announcing it was now half past 10 o'clock.
(not comparable)Roughly (but not exactly) hourly: occurring around every sixty minutes.
Origin
From semi- + hourly.From semi- + hourly.
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