1
A lazy way of saying you're forced to do something. You use it to act like you're in on it, even if you're not.
"I'm going to the party out of obligation," he said, like he was a hero and not a coward.
She said she'd help with the move out of obligation. That means she's gonna whine the whole time.
He took the job out of obligation. He probably still hates his boss.