It does not seem to have any useful objective definition.
There are statements which purport to be definitions of poverty. Most of them are not absolute, or even objective. Most of them are simply relative to the median in society. They define anyone who cannot afford the necessities as poor. Then they define any product which is owned by more than two thirds of the population as a necessity .This is a meaningless measurement - defining poverty to be the bottom 30 percentile of income, and then screaming that 30 percent of people are in poverty is logically stupid, though obviously politically beneficial. A bizarre effect of defining poverty as a percentage of average weekly earnings is that poverty increases if the minimum wage is increased. Clearly this is a non-sensical definition of poverty.
Given free will, some people will choose to work hard, some will choose to be lazy, some will choose to be honest, some will choose to steal. Some will squander their resources on alcohol and drugs, others will choose to use their resources to create other resources. Some will choose to become rich, some will choose to be poor. The greater the amount of free choice, the wider the wealth distribution (the gap between rich and poor) will be.
The only way to eliminate poverty as defined by this formula is to force everyone to own exactly the same things (see equality). There are communist ideologies which have supported this, but few intelligent people condone them.
Communist countries which have tried to reduce the wealth distribution have simply changed the currency. Material goods have been hard to come by, but the fundamental commodity, power, has been in no short supply, and those who have it have shown little restraint in using it.
Without objective standards, it is really only sensible to talk about poverty in relative standards. One group may be poorer than another.