(with) hat in hand
In a meek or submissive manner. (The removal of one's hat is typically a gesture of respect.) I can't believe I have to go back to my old boss with hat in hand and ask for my job back.
(with) hat in hand
Fig. with humility. (Fig. on the image of someone standing, respectfully, in front of a powerful person, asking for a favor.) She stormed off but came back with hat in hand when she ran out of money. We had to go hat in hand to the committee to get a grant for our proposal.
hat in hand
Also, cap in hand. In a humble manner. For example, They went to her, hat in hand, asking for a change of assignment. This expression alludes to removing one's headgear as a sign of respect and has survived the era of doffing one's hat. [c. 1700]
hat in hand
In a humble manner; humbly.