Use the adjective attentive to describe someone who is alert and paying attention: “Attentive observers of the play used clues given in the first scenes of the play to guess the identity of the murderer.”

You probably notice that the word attentive looks a lot like the noun attention. It’s easy to remember how to use attentive when you know that the words share related meanings. Use the adjective attentive to describe someone who is full of attention, watching and listening carefully, such as an attentive student who takes great notes and asks questions when something isn't clear.

Definitions of attentive

adj taking heed; giving close and thoughtful attention

heedful, paying attention, thoughtful
heedless, unheeding
marked by or paying little heed or attention
careless, regardless
(usually followed by `of') without due thought or consideration
deaf, indifferent
(usually followed by `to') unwilling or refusing to pay heed
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adj (often followed by `to') giving care or attention

attentive to details”
“the nurse was attentive to her patient”
“an attentive suitor”
absorbed, captive, engrossed, enwrapped, intent, wrapped
giving or marked by complete attention to
advertent, heedful
giving attention
paying close attention especially to details
excessively solicitous
showing hovering attentiveness
feeling or showing worry or solicitude
showing a lack of attention or care
absent, absentminded, abstracted, scatty
lost in thought; showing preoccupation
distracted, distrait
having the attention diverted especially because of anxiety
dreamy, moony, woolgathering
dreamy in mood or nature
drowsy, oscitant, yawning
showing lack of attention or boredom
forgetful, oblivious
failing to keep in mind
marked by lack of attention or consideration or forethought or thoroughness; not careful
characterized by neglect and undue lack of concern
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