Approval, agreement, or instruction to begin or proceed.

“You can start as soon as you get the go-ahead from the president.”

Progressive; exerting leadership.

“I work for a very go-ahead company that's always looking for new ideas.”

Dashing; energetic.

Being a score which gives the scoring team or player the lead in the game.

“The pitcher gave up the go-ahead run in the top of the ninth inning.”