Have one in the oven phrase informal
if a woman has one in the oven, she is pregnant.
She quit coffee when she had one in the oven.
My wife is having a bun in the oven, and this is our first child.
Used to say that someone is pregnant
The verb "have" must be conjugated according to its tense.
To do domething based on your emotions rather than for rational reasons
I can't believe that Tom beat his classmate. He's always the one who let his heart rule his head.