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Definition

(Science: Cell Biology, Genetics)

noun

(1) The number of chromosomes in a gamete of an organism, symbolized by n.

(2) A cell or an organism having half of the number of chromosomes in somatic cells.

adjective

Of or pertaining to a condition in which there is only half of the complete set of chromosomes in somatic cells.

Supplement

For instance, a human germ cell (a sperm or an egg cell) is haploid, which means it contains only one of each of the 23 chromosomes of the human genome, or it only has half the diploid (2n) number of a human somatic cell (which is 46). Gametes being haploid are essential particularly during fertilization. The union of two sex cells, each with only haploid number of chromosomes, results in a diploid zygote. The integrity of chromosomal number throughout generations is eventually preserved.

Word origin: From Greek haplous, single.
Related forms:" haploidy (noun), haploidic (adjective).
Compare:" diploid, polyploid.
See also:" ploidy, monoploid, dihaploidy, polyhaploidy.