hap·loid / ˈhapˌloid/ Genetics • adj. (of a cell or nucleus) having a single set of unpaired chromosomes. Compare with diploid. ∎  (of an organism or part) composed of haploid cells.• n. a haploid organism or cell.DERIVATIVES: hap·loi·dy n.

haploid Term describing a cell that has only one member of each chromosome pair. All human cells except gametes are diploid, having 46 chromosomes. Gametes are haploid, having 23 chromosomes. The body cells of many lower organisms, including many algae and single-celled organisms, are haploid. See also alternation of generations; meiosis

haploid Applied to a cell nucleus that contains one of each type of chromosome, i.e. one set of chromosomes, designated n. Gametes are haploid, in contrast with most somatic cells, which usually have some multiple of this number, usually 2n (diploid), but sometimes 3n (triploid), 4n (tetraploid), or many-n (polyploid). A haploid cell thus has only one chromosome set, and a haploid organism contains only haploid cells.

haploid Describing a nucleus, cell, or organism with a single set of unpaired chromosomes. The haploid number is designated as n. Reproductive cells, formed as a result of meiosis, are haploid. Fusion of two such cells (see fertilization) restores the normal (diploid) number.

haploid (monoploid) (hap-loid) adj. describing cells, nuclei, or organisms with a single set of unpaired chromosomes. In humans the gametes are haploid following meiosis. Compare diploid, triploid.
—haploid n.