xenogenesis

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The supposed production of offspring markedly different from either parent.
2. n. See alternation of generations.

Century Dictionary and Cyclopedia

1. n. The generation of offspring which pass through an entirely different life-cycle from that of the parents, and never exhibit the characters of the latter: a mode of biogenesis supposed by Milne-Edwards to occur, but not proved to have any existence in fact.

Wiktionary

1. n. A foreign origin or source.
2. n. biology The production of an offspring that is unlike either of its parents.

GNU Webster's 1913

1. n. Same as heterogenesis.
2. n. The fancied production of an organism of one kind by an organism of another.

WordNet 3.0

1. n. the alternation of two or more different forms in the life cycle of a plant or animal