The documents are only available to people with 'security clearance' [=special permission given only to people who are approved to know or see secret things] from the government.
The car has a 'road/ground clearance' of seven inches. [=the bottom of the car is seven inches above the road/ground]
You'll have to get 'clearance' [='approval'] from management to go ahead with the project.
(..) I need to get back to the PEOC. - Is Tom gonna be in there? - Well, it is his meeting. - Well, then I'm coming with you. Sorry, Emily, but in there, it's code-word clearance only. I've been with Secretary Kirkman's staff for three years. It's President Kirkman now, and you're not authorized. (..)2016 TvShow: Designated Survivor Title: Pilot Season: 1 Episode 1