1.NounThe act of arousing or the state of being aroused.
"bodily arousal; emotional arousal; to influence the arousal of brain and behavior"
2.NounSexual arousal.
"Some people get arousal from the depiction of feet."
3.NounA physiological and psychological state of being awake or reactive to stimuli, including elevated heart rate and blood pressure and a condition of sensory alertness, mobility and readiness to respond.
4.NounArousal from sleep or hibernation.
"the mechanism for arousal from sleep; The animal undergoes regular spells of arousal."