national grid 
noun British
1The network of high-voltage power lines between major power stations.Right now Lewis is connected to the national grid by a one-way powerline that enters the water at Ardmore bay on Skye....
- When Fawley power station is on-line it supplies 500 megawatts to the national grid - that's more or less enough power to keep Southampton alight.
- National Grid revealed today that the power line was now carrying electricity to supply the national grid.
2The metric system of geographical coordinates used in maps of the British Isles.
- colour constancy
- colour contrast
- colour-coordinate
- colour-coordinated
- colour-coordinating
- colour coordination
- colour-correct
- colour-corrected
- colour correction
- colour cup
- colour-defective
- colour-de-roy
- colour diagram
- colour difference
- colour disc
- colour discrimination
- colour doctor
- colour duster
- colour dusting
- coloured
- coloured audition
- coloured clothes
- coloured hearing
- coloured pencil
- colour emphasis