Alertness

n. readiness; wakefulness; carefulness

Alertness is the state of paying close and continuous attention. It is the opposite of inattention, which is failure to pay close attention to details or making careless mistakes when doing work or other activities, trouble keeping attention focused during tasks, appearing not to listen when spoken to, failure to follow instructions or finish tasks, avoiding tasks that require a high amount of mental effort and organization, such as projects, frequently losing items required to facilitate tasks or activities, such as supplies, excessive distractibility, forgetfulness, procrastination i.e. inability to begin an activity, difficulties with activities (cleaning, administrative, etc.), difficulty falling asleep which may be due to too many thoughts at night, frequent emotional outbursts, easily frustrated, and easily distracted.
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Alertness the mental state of aroused awareness. Inferred in animals. [more]Alertness - Community and Resources

Noun
1. the process of paying close and continuous attention
(synonym) watchfulness, vigilance
(hypernym) attention
(hyponym) jealousy
2. a state of readiness to respond; "alerting was indicated by the desynchronization of the EEG"
(synonym) alerting
(hypernym) arousal
3. lively attentiveness
(synonym) on the qui vive
(hypernym) attentiveness

(n.)
The quality of being alert or on the alert; briskness; nimbleness; activity.