Favour
Definition 1 of 5
Pro Tip 1/3
Not Obligatory
A favour is kindness without being forced or paid for doing it. She volunteered to proofread my essay, that was a huge favour.
Pro Tip 2/3
Unconditional Help
When doing a favour, you should not expect anything in return. I can house-sit for you as a favour; just enjoy your vacation!
Pro Tip 3/3
Gratitude Expression
It's polite to thank someone who grants you a favour. Thanks for picking up my mail - I owe you a favour.