heat of pas·sion: an agitated state of mind (as anger or terror) prompted by provocation sufficient to overcome the ability of a reasonable person to reflect on and control his or her actions – called also heat of blood, heat of passion on sudden provocation, hot blood, sudden heat, sudden heat of passion, sudden passion; see also manslaughter compare cold blood, cool state of blood
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.