In biology and specifically, genetics, the term hybrid has several meanings, all referring to the offspring of sexual reproduction.
- In general usage, hybrid is synonymous with heterozygous: any offspring resulting from the mating of two distinctly homozygous individuals
- a genetic hybrid carries two different alleles of the same gene
- a structural hybrid results from the fusion of gametes that have differing structure in at least one chromosome, as a result of structural abnormalities
- a numerical hybrid results from the fusion of gametes having different haploid numbers of chromosomes
- a permanent hybrid is a situation where only the heterozygous genotype occurs, because all homozygous combinations are lethal.