1) Alerting 2) Caution 3) Nimbleness 4) Vigilance 5) Watchfulness 1) Attention 2) Devil 3) Opposite of torpor 4) Product of caffeine pills 5) Quality given by pep pills 6) Show new spirit 7) State of being ready 8) State of caution 9) Ten lasers focused attention 10) Vigilance 11) Watchfulness 
Alertness is the state of active attention by high sensory awareness such as being watchful and prompt to meet danger or emergency, or being quick to perceive and act. It is related to psychology as well as to physiology. A lack of alertness is a symptom of a number of conditions, including narcolepsy, attention deficit disorder, chronic fatigue s...
• (n.) The quality of being alert or on the alert; briskness; nimbleness; activity.
A·lert'ness noun The quality of being alert or on the alert; briskness; nimbleness; activity. 
[n] - a state of readiness to respond 2. [n] - lively attentiveness
sharp-sightedness noun lively attentiveness