1. (noun) a cross between an organism whose genotype for a certain trait is unknown and an organism that is homozygous recessive for that trait so the unknown genotype can be determined from that of the offspring

• test-cross

1. (noun) a cross between an organism whose genotype for a certain trait is unknown and an organism that is homozygous recessive for that trait so the unknown genotype can be determined from that of the offspring

• cross
• crossbreeding
• crossing
• hybridisation
• hybridization
• hybridizing
• interbreeding