noun

• (Sussex) A sheltered area of coast between two cliffs (mostly restricted to place names).
  "At Birling Gap we can stop and go have a picnic on the beach."
• (baseball) The regions between the outfielders.
  "Jones doubled through the gap."
• (Australia, for a medical or pharmacy item) The shortfall between the amount the medical insurer will pay to the service provider and the scheduled fee for the item.
  "Under bulk billing the patient does not pay a gap, and the medical practitioner receives 85% of the scheduled fee."
• (Australia, usually written as "the gap") The disparity between the indigenous and non-indigenous communities with regard to life expectancy, education, health, etc.

verb

• (transitive) To notch, as a sword or knife.
• (transitive) To make an opening in; to breach.
• (transitive) To check the size of a gap.
  "I gapped all the spark plugs in my car, but then realized I had used the wrong manual and had made them too small."
• (transitive, intransitive, slang, especially video games, motor racing) To surpass (someone or something) by a considerable margin.
  "Honestly K&C could release today with like a bit more SOT buffs and they'd probably still gap a lot of the game"

verb

• (intransitive, transitive, US, slang, dated) To stare or gape.
  "Well, dey would all begin stretchin' and gappin', and den some of dem would say, with a gap and another stretch: […]"