on standby

Idioms  

1. Ready and waiting, as in We've got three more painters on standby. This expression originated in the navy in the 1940s, where it referred to someone being ready to come on duty as soon as required. From about 1960 it began to be widely used in aviation for a passenger waiting to take the first available seat on a full flight.

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Example Sentences

Police with riot helmets could be seen on standby near the demonstration, where some protesters marched waving Palestinian flags.

From Barron's

As locals watched a darkening sky, police patrolled streets empty of all but stray cats, while emergency services stood on standby on the edge of the red zone.

From Barron's

It added there will be additional roads and river team staff on standby to respond to incidents.

From BBC

Soldiers are on standby for possible deployment to Minneapolis, a US defence official has told CBS News, the BBC's US partner.

From BBC

To ensure continuity of operations in the event of an attack, each of Fire Point’s factories has at least one exact copy, Shtilerman said, with the same equipment on standby in case a key link in the production chain is destroyed.

From The Wall Street Journal