General Antonyms:
* Slow: This is a very general antonym, meaning taking a long time.
* Delayed: This implies a specific delay in a process or action.
* Late: Similar to delayed, but often refers to a specific time.
* Tardy: This implies a habitual tendency to be late or slow.
* Unhurried: This emphasizes a lack of urgency or rush.
* Lagging: This suggests a falling behind in progress.
* Dilatory: This implies a deliberate procrastination or delaying tactics.
Specific Antonyms depending on context:
* Neglectful: If prompt refers to a responsibility, neglectful is an antonym.
* Indifferent: If prompt refers to a response, indifferent is an antonym.
* Unresponsive: Similar to indifferent, this implies a lack of reaction.
* Careless: If prompt refers to carefulness, careless is an antonym.
Example:
* Prompt: She responded promptly to my message.
* Antonym: She was slow to respond to my message.
The best antonym for "prompt" will depend on the specific situation and the intended meaning.