WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
noun.
creation by the physical union of male and female gametes; of sperm and ova in an animal or pollen and ovule in a plant
noun.
making fertile as by applying fertilizer or manure
Word Usage
"The term "fertilisation" could be taken to mean anything from the penetration of the egg by the sperm, to the implantation of the egg into the uterus which happens later."