Technical term in genetics for an organism with two different alleles at a locus. Compare ヘテロ接合体, which is the katakana loanword equivalent.
See also: ヘテロ接合体
For this locus, the individual is a heterozygote.
Compound of 異型 (ikei, 'hetero-type') + 接合体 (setsugōtai, 'zygote' or 'conjugate'), calqued from English 'heterozygote'.