Organisms that can make both sperm and oocytes and can self-fertilize. C. elegans has both hermaphrodites and males. The male can mate with hermaphrodites to produce cross progeny.
One of several alternative forms of a gene occupying a given locus on a chromosome, such as zyg-1(oj-7), zyg-1(it4). Lewin, B. (1994). Genes V. New York, NY: Oxford University Press. p.1235