What is Hunger?

Legal Definition
In politics, humanitarian aid, and social science, hunger is a condition in which a person, for a sustained period, is unable to eat sufficient food to meet basic nutritional needs.

Throughout history, portions of the world's population have often experienced sustained periods of hunger. In many cases, this resulted from food supply disruptions caused by war, plagues, or adverse weather. For the first few decades after World War II, technological progress and enhanced political cooperation suggested it might be possible to substantially reduce the number of people suffering from hunger. While progress was uneven, by 2000 the threat of extreme hunger subsided for many of the world's people. According to the WFP some statistics are that, "Some 795 million people in the world do not have enough food to lead a healthy active life. That's about one in nine people on earth. The vast majority of the world's hungry people live in developing countries, where 12.9 percent of the population is undernourished."

Until 2006, the average international price of food had been largely stable for several decades. In the closing months of 2006, however, prices began to rise rapidly. By 2008, rice had tripled in price in some regions, and this severely affected developing countries. Food prices fell in early 2009, but rose to another record high in 2011, and have since decreased slightly. The 2008 worldwide financial crisis further increased the number of people suffering from hunger, including dramatic increases even in advanced economies such as Great Britain, the Eurozone and the United States.

The Millennium Development Goals included a commitment to a further 50% reduction in the proportion of the world's population who suffer from extreme hunger by 2015. As of 2012, this target appeared difficult to achieve, due in part to persistent inflation in food prices. However, in late 2012 the UN's Food and Agriculture Organization (FAO) stated it is still possible to hit the target with sufficient effort. In 2013, the FAO estimated that 842 million people are undernourished (12% of the global population). Malnutrition is a cause of death for more than 3.1 million children under 5 every year. UNICEF estimates 300 million children go to bed hungry each night; and that 8000 children under the age of 5 are estimated to die of malnutrition every day.
-- Wikipedia
Legal Definition
The desire for taking food. Hunger is no excuse for larceny. 1 Hale, P. C. 54; 4 Bl. Com. 31. But it is a matter which applies itself strongly to the consciences of the judges in mitigation of the punishment.

2. When a person has died, and it is suspected he has been starved to death, an examination of his body ought to be made, to ascertain whether or not he died of hunger. The signs which usually attend death from hunger are the following: The body is much emaciated, and a foetid, acrid odor exhales from it, although death may have been very recent. The eyes are red and open, which is not usual in other causes of death. The tongue and throat are dry, even to aridity, and the stomach and intestines are contracted and empty. The gall bladder is pressed with bile, and this fluid is found scattered over the stomach and intestines, so as to tinge them very extensively. The lungs are withered, but all the other organs are generally in a healthy state. The blood vessels are usually empty. Foder´, tom. ii. p. 276, tom. iii. p. 231; 2 Beck's Med. Jur. 52; see Eunom. Dial. 2, §47, p. 142, and the note at p. 384.
-- Bouviers Law Dictionary