alertness Meaning, Definition & Usage

1. noun the process of paying close and continuous attention
   vigilance; watchfulness; wakefulness.
   
   • wakefulness, watchfulness, and bellicosity make a good hunter
   • vigilance is especially susceptible to fatigue
2. noun a state of readiness to respond
   alerting.
   
   • alerting was indicated by the desynchronization of the EEG
3. noun lively attentiveness
   sharp-sightedness; on the qui vive.
   

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