1. having official approval.

We won't get paid until the contract is signed and sealed.

Usage notes: usually refers to an agreement or contract

2. completed or made final.

He'll make a decision next week, but until then the matter isn't signed and sealed.

Etymology: based on a literal meaning of sign and seal (= to put your signature and an official mark on a document that shows it is legal)

• let someone be
• let someone down
• let someone go
• let someone have it
• let someone in on
• let someone in on something
• let someone off
• let someone off easy
• let someone off the hook
• let someone slide
• let someone slip through fingers
• let someone slip through your fingers
• let something be
• let something go
• let something ride
• let something slide
• let something slip
• let something slip through fingers
• let something slip through your fingers
• let something speak for itself
• let something speak for themselves
• let speak for itself
• let speak for themselves
• let's see
• letter of the law