What does "sign off on" mean?

To give formal approval or agreement to something - especially before it can proceed.

"We need the director to sign off on this before we launch."
"Has legal signed off on the contract?"
"I'm waiting for her to sign off on the budget."

• Sign off on something: approve it formally
• Sign off: finish and leave (end of day/shift/email): "I'll sign off here." Also at the end of an email or letter.

In organisations, signing off creates a formal record that someone with authority has approved something. It protects both parties and creates accountability.

"We're waiting for the client sign-off."
"The project needs three levels of sign-off."

• "Approve" - direct and formal
• "Give the green light" - informal approval: "The CEO gave it the green light."
• "Rubber-stamp" - approve without real scrutiny (slightly negative connotation)
• "Sign" - literal signature: "Can you sign this?"

Professional. Common in legal, finance, creative, and project management contexts.