What is the definition of extravagance (Israf) and squandering (Tabdhir), and what is their degree? Is donating money to the poor considered extravagance and squandering if the family is in need of it, or if something was promised to be bought for a child and then it was donated?

Extravagance is exceeding the limit in consuming permissible things, and it has been forbidden by more than one scholar. It is not permissible to throw away leftover edible food unless there is a fear of harm from consuming it, or if people find it repulsive, in which case it should be given to animals. If there is no way to dispose of it, then we hope there is no harm in throwing it away. The matter can be addressed by cooking food according to need. Extravagance does not include buying something and then realizing it is not needed, or donating money to the poor, or not buying what children were promised due to donating money to the poor.