Term: zygote: (genetics) the diploid cell resulting from the union of a haploid spermatozoon and ovum (including the organism that develops from that cell)
Broader: cell: (biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals | Unrelated: pythium: any fungus of the genus Pythium