Wikipedia
Infaq
ʾInfāq (إنفاق) is an Arabic word meaning spending, disbursement. simply to please God without asking for any favor or hoping for a return. The word ʾinfāq is mentioned once in the Qurʾān in Sūrat al-ʾIsrāʾ, verse 100. The imperative form of the verb (ʾanfiqū) (أَنفِقُوا) appears 18 times in the Qurʾān. It is different from Zakat, which is obligatory on Muslims, or Sadaqah, which is charity for obtaining specific return or protection from some adverse event.