The definition of hell-for-leather is done with all of one's energy, or at full speed.(adjective)
An example of something done hell-for-leather is a final sprint to win a major marathon.
Hell-for-leather is defined as done in a very quick way, or in a way that exerts all of one's energy.(adverb)
An example of hell-for-leather used as an adverb is in the phrase "hell for leather running," which means running at one's highest speed.
See hell-for-leather in Webster's New World College Dictionary
See hell-for-leather in American Heritage Dictionary 4
adverb & adj.
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