around/round the clock
(a)round the clock
Fig. continuously for twenty-four hours at a time. The priceless jewels were guarded around the clock. Grandfather was so sick that he had to have nurses round the clock.
round the clockor
around the clock
COMMON If you do something round the clock or around the clock, you do it continuously, throughout the day and night. Fire crews were working round the clock to bring the huge blaze under control. Detectives watched him around the clock. Note: Round-the-clock and around-the-clock can be used before a noun to describe work that is being done continuously, throughout the day and night. Staff alerted police and a round-the-clock surveillance of the four men began. We can't afford to give you around-the-clock protection.
round (or around) the clockall day and all night; ceaselessly.
1992 Susan Sontag The Volcano Lover The mountain was…guarded round the clock by a ring of armed soldiers mounted on nervous horses.