In reply to goodbikegear:
A hybrid is mix of two animals or plants of different breeds, varieties, species or genera. Using genetics terminology, it may be defined as follows:
In general usage, hybrid is synonymous with heterozygous: any offspring resulting from the breeding of two genetically distinct 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.
Whereas a road bike is type of bicycle.