benevolence; charitable spirit
A somewhat formal noun referring to a compassionate, giving disposition. Often used in contexts of philanthropy or moral character.
I was impressed by his charitable spirit.
Many people donate out of benevolence.
博愛 means 'universal love' or 'philanthropy' and is broader in scope, often used in philosophical or religious contexts, whereas 慈善心 focuses on the personal quality of being charitable.
Compound of 慈善 (charity, benevolence) and 心 (heart, spirit). The exact historical derivation is uncertain, but the word transparently combines these elements to mean 'benevolent heart'.