What does it mean when something is redlined?

1. To refuse to provide mortgages, insurance, or other goods or services to areas deemed a poor economic risk, particularly when the residents are nonwhite. 2. To reach the maximum engine speed at which an engine is designed to be safely operated: The car redlined at 80 miles per hour in fourth gear.

How do you write redline?

In the toolbar at the top of the screen, click the "Review" tab. This tab contains tools to help with spell checking and editing, including the "Track Changes" feature. Click the "Track Changes" button to enable Track Changes. This feature places a red line in the margins next to any edited text.