Question

Some organisms feed on other organisms without immediately killing the organism. What term describes this act?

Answer 1

I believe the answer would be "parasitism."

Answer 2

The answer to your question would be option 2: Parasitism.

Parasitism is the act of an organism feeding off another organism, that does not kill the host organism at first but may eventually, if not treated.

Predation is the act of immediately killing another organism for your benefit.

Mutualism is where two organism benefit each other when involved.

Commensalim is two organism where only one organism benefits, but it does not give any affect to the other organism.

Thus, I feel Parasitism would best fit your description!

Hope this helps!