Quick answer
Purposely means on purpose — deliberately rather than by accident. Purposefully means with evident determination and direction. She purposely left early (she meant to); she walked purposefully to the door (with resolve). One is about intention, the other about manner.
The core difference
Both come from purpose, but describe different things.
- purposely — deliberately: He purposely ignored the question.
- purposefully — with determination and direction: She strode purposefully across the room.
The test
Substitute deliberately and then with determination. Only one will fit. "He deliberately ignored the question" works; "he ignored it with determination" does not.
Why purposefully is over-used
It is the longer word, and longer words attract writers wanting emphasis. But it makes a claim about manner and resolve that purposely does not — so using it where you mean "on purpose" describes something you probably did not observe.
Frequently asked questions
Which one means "on purpose"?
Purposely. Purposefully means with determination and evident direction.
How do I check which to use?
Substitute deliberately. If the sentence still works, you want purposely.
Can an action be both?
Yes — someone can purposely and purposefully walk out. But the words are describing different aspects: intention and manner.
