external fertilization

fertilization /fer·ti·li·za·tion/ (fer″tĭ-lĭ-za´shun) impregnation; union of male and female gametes to form the diploid zygote, leading to development of a new individual.

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external fertilization  union of the gametes outside the bodies of the originating organisms, as in most fish.

internal fertilization  union of the gametes inside the body of the female, the sperm having been transferred from the body of the male by an accessory sex organ or other means.

in vitro fertilization  removal of a secondary oocyte, fertilization of it in a culture medium in the laboratory, and placement of the dividing zygote into the uterus.

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external fertilization,

the union of male and female gametes outside the bodies from which they originated, such as occurs in frogs and most fish.