the.com/standby

The seat you get only if someone else fails to show up.

means Someone or something kept ready and waiting to be used only if the primary option falls through.

from Built from 'stand' plus 'by,' meaning literally to stand near at hand, ready for action — the phrase 'stand by' was used as a readiness command (notably in nautical and military contexts, as in 'stand by to fire') centuries before it hardened into the single noun 'standby' we use for backup plans, spare generators, and unlucky airline passengers hovering at the gate.

origin
1920s aviation term for reserve pilots
odds booster
full flights make standby success basically a lottery
power mode
electronics sip power while pretending to be off
airline trick
overbooking exists partly to fill standby seats
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