stand to1
[often in imperative] Military Stand ready for an attack, especially one before dawn or after dark: orders came to the guardroom to stand to...
- Ordered to ‘stand-to!’ just before dawn, the men would be assigned to stand on the fire step dug into the wall of the trench.
- All British battalions in the front line of 28th Division were ordered to ‘stand to’.
- The defenders were ordered to stand to.
See parent entry: stand
stand-to2 
noun [mass noun] Military
1The state of readiness for action or attack.Complying with established stand-to times, support platoon members begin to prepare....
- In response to the emerging threat, soldiers went on stand-to from 0200 until 0500 hours.
- They adopted their stand-to positions in slit trenches and machine gun pits.
1.1The formal start to a day of military operations: the sky was getting light and it would soon be stand-to...
- Most infantrymen are accustomed to the traditional stand-to an hour before and after sunrise.
- We had one 20 minute break for quiet time at stand-to - then kept going into the night - it was a lot slower and a bit more dangerous.
