breakneck

[ breyk-nek ]
/ ˈbreɪkˌnɛk /

adjective

reckless or dangerous, especially because of excessive speed; hazardous: He raced through the streets at breakneck speed.

Origin of breakneck

First recorded in 1555–65; break + neck
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for breakneck

British Dictionary definitions for breakneck

breakneck
/ (ˈbreɪkˌnɛk) /

adjective

(prenominal) (of speed, pace, etc) excessive and dangerous
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012