General Antonyms:
* Inattentive: This is the most direct opposite, meaning not paying attention.
* Distracted: This implies a lack of focus and being easily drawn away from something.
* Uninterested: This implies a lack of engagement or care.
* Neglectful: This suggests a lack of care or attention to someone or something.
Context-Specific Antonyms:
* Absentminded: This implies a lack of attention due to being preoccupied with other things.
* Unresponsive: This implies a lack of reaction or acknowledgement.
* Indifferent: This implies a lack of interest or feeling.
* Dismissive: This implies a lack of respect or consideration.
The best antonym for "attentive" will depend on the specific situation and what you want to convey.