statistics again
Yes, the definition of poverty is local and relative, and is set by each nation when it compiles its own statistics.
National estimates of the percentage of the population lying below the poverty line are based on surveys of sub-groups, with the results weighted by the number of people in each group. Definitions of poverty vary considerably among nations. For example, rich nations generally employ more generous standards of poverty than poor nations.
Since any attempt to define absolute poverty must be relative, a more meaningful measure of the economic health of a population--"economic justice", as some people put it--is to be found in the distribution of income in a given society. It's entirely relevant because it sheds some light on why people in a given society are poor: Is it of necessity, when the entire society is poor? Or is it due to an uneven economic playing field, when a society is prosperous overall but the prosperity is not shared? In other words, does the society's rising tide really lift all boats?
A nation that's poor overall has a very good (and blindingly obvious) excuse for its poverty, while a wealthy nation with a significant proportion of poor people has some explaining to do.
NationMaster provides distribution of income stats, of course. The by family income table shows what's long been known: Of 122 nations, the US ranks 36th in maldistribution of income. Meet the neighbors: #33: Philippines, #34 Costa Rica, #35 Cote d'Ivoire, #37 Uruguay, #38 Cameroon, #39 Kenya, #40 Mongolia...a nation is known by the economic company it keeps. Imagine: Mongolia, Kenya, Cameroon and Uruguay have a more equitable distribution of income than America.
Welcome to the plantation!