A cry is a sustained, voiced utterance, usually of around one second or more (reports vary), the duration of an outward breath. Think of a baby’s ‘waaa.’ … Cries repeat at intervals of about one second, roughly the duration of one respiratory cycle … A laugh, in contrast, is a chopped (not sustained), usually voiced exhalation, as in ‘ha-ha-ha,’ in which each syllable (‘ha’) lasts about 1/15 second and repeats every 1/5 second.