Question: Who coined the term/word "altruism?" Was it Kant and if so where is this information?
Answer: According to the Oxford English Dictionary, the term was coined by Auguste Comte, the 19th-century French sociologist and philosopher, known for his philosophy of "Positivism." It is in Compte's sense of sacrifice to society or taking the good of others as the highest good that Objectivism speaks of "altruism." Many today use the term to mean this, or something less clear-cut, such as basic decency or generosity.
For more historical details about Comte and the evolution of the use of the term "altruism," I recommend " Altruism in Auguste Comte and Ayn Rand " by Robert Campbell, The Journal of Ayn Rand Studies, Volume 7 Number 2, 357-369.