Live means energised or able to be energised. IEC rules count the neutral as a live part because it is meant to carry current in service, while a PEN conductor is treated as protective rather than live. In practice the word marks what may not be touched: live working is allowed only under special procedures, with insulated tools and qualified staff. British usage also calls the phase conductor the live, as in live, neutral and earth.
Heard on the job
Cable's live from the far end through the backfeed, nobody cuts anything until we prove it dead.
Also heard as
- energised
- energized
- hot
Do not mix it up with
- Dead: Dead means isolated, tested and confirmed free of voltage, not simply switched off.