break one's neck, to

break one's neck (to do something)

 and break one's back (to do something)
Fig. to work very hard to accomplish something. I broke my neck to get here on time. There is no point in breaking your back. Take your time.
See also: break, neck
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

break one's neck

see under break one's back.
See also: break, neck
The American Heritage® Dictionary of Idioms by Christine Ammer.

break (one's) neck

To make the utmost possible effort.
See also: break, neck
American Heritage® Dictionary of the English Language, Fifth Edition.

break one's neck, to

To hurry as fast as one can, to proceed with reckless speed. The same idea is conveyed by breakneck pace, the word breakneck dating from the sixteenth century. At that time, however, to break someone’s neck also meant to overpower or overwhelm them. This was Sir Geoffrey Fenton’s meaning when he wrote, “To breake the necke of the wicked purposes and plots of the French” (The History of Guicciardini, 1579).
See also: break
The Dictionary of Clichés by Christine Ammer
See also:
  • breaking
  • be/go back to square one
  • back to square one
  • back to the salt mines
  • echo back to
  • carry (one) back
  • carry back
  • come back and see us
  • a while back
  • back at (something or some place)