Tra từ alert - Từ điển WordNet v3.1

I - noun

1. condition of heightened watchfulness or preparation for action
- bombers were put on alert during the crisis
• Syn:
qui vive
• Hypernyms:
readiness, preparedness, preparation
• Hyponyms:
air alert, red alert, strip alert
2. a warning serves to make you more alert to danger
• Syn:
alerting
• Hypernyms:
warning
• Instance Hyponyms:
Emergency Alert System, EAS
3. an automatic signal (usually a sound) warning of danger
• Syn:
alarm, warning signal, alarum
• Hypernyms:
signal, signaling, sign
• Hyponyms:
torpedo, air alert, burglar alarm, fire alarm, foghorn,
fogsignal, horn, red flag, siren, tocsin, alarm bell

II - verb

warn or arouse to a sense of danger or call to a state of preparedness (Freq. 9)
- The empty house alarmed him
- We alerted the new neighbors to the high rate of burglaries
• Syn:
alarm
• Derivationally related forms:
alarm (for: alarm)
• Hypernyms:
warn
• Hyponyms:
wake
• Verb Frames:
- Somebody ----s somebody
- Something ----s somebody

III - adjective

1. engaged in or accustomed to close observation (Freq. 7)
- caught by a couple of alert cops
- alert enough to spot the opportunity when it came
- constantly alert and vigilant, like a sentinel on duty
• Syn:
watchful
• Ant:
unalert
• Similar to:
argus-eyed, open-eyed, vigilant, wakeful, fly,
heads-up, wide-awake, lidless, sleepless
• See Also:
awake, lively, wary
• Derivationally related forms:
watchfulness (for: watchful), alertness
2. quick and energetic
- a brisk walk in the park
- a lively gait
- a merry chase
- traveling at a rattling rate
- a snappy pace
- a spanking breeze
• Syn:
brisk, lively, merry, rattling, snappy,
spanking, zippy
• Similar to:
energetic
• Derivationally related forms:
zip (for: zippy), liveliness (for: lively), briskness (for: brisk)
3. mentally perceptive and responsive
- an alert mind
- alert to the problems
- alive to what is going on
- awake to the dangers of her situation
- was now awake to the reality of his predicament
• Syn:
alive, awake
• Similar to:
aware, cognizant, cognisant
• Derivationally related forms:
aliveness (for: alive), alertness