Meep or Meap
A condition shared my few, but heard by many; it is the sound made by a convulsing single hiccup, yet the inflection is unsynchopated. The sufferer is powerless to control it and it's onset is as unpredictable as a hiccup. The diaphram spasms, causing the sufferer to inhale sharply, making a very loud, pitched, gasp. Milder form of this condition is exhibited by people who have over eaten or drank too much. True suffers are very distinct and are often mistaken by witnesses as having been surprised or hurt. Though often painful, the occurances are unavoidable, untreatable, unsymptomatic, exhibit no lasting health effects, and have only been discovered to afflict women.
You are riding the train and a woman a few feet away gasps so loudly, it draws the attention of the entire car. Everyone turns to lend assistance, but she simply says "Excuse me, it's just a meep" this is called Meep or meap. However you want to spell it.