Headroom
Part of speech: noun
Definition: the vertical clearance above someone's head, as in a tunnel, doorway etc the ability of a system to reproduce loud sounds free of distortion; dynamic headroom
Clearance
Part of speech: noun
Definition: The act of clearing or something (such as a space) clearedThe distance between two moving objects, especially between parts of a machineThe height or width of a tunnel, bridge or other passage, or the distance between a vehicle and the walls or roof of such passage; a gap, headroom.A permission for a vehicle to proceed, or for a person to travel.A permission to have access to sensitive or secret documents or other informationA sale of merchandise at a reduced price.The settlement of transactions involving securities or means of payment such as checks by means of a clearing house.The removal of harmful substances from the blood; renal clearance.The act of potting all the remaining balls on a table at one visit.
Example sentence: The world is not kind to whistleblowers - a term of art with particular resonance in football, the most hierarchical and repressive of organized sports, a world of 'systems' and 'programs' and scripted plays, where reading a medical report requires a security clearance, and practice fields are patrolled like Guantanamo Bay.