Monoicous

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The general meaning of monoecious or monoicous, monocous (from Greek: mono, single, oikos, house) is having male and female reproductive organs in the same plant or animal, as opposed to dioecious or diocious (Greek: dia (diairo: "divide") + oikos, "house").

Synonymous with "mono-*" is syno-*. Synonymous with "dio-*" are paro-* and hetero-*. For example, "synoecious", "heteroecious", and other combinations.

In zoology, the preferred terminology has become hermaphrodite, rather than "monoecious", while botany has a more specific usage of the terms. An exception are lower animals, e.g., the phylum of annelids (that covers worms and leeches): they may be dioecious (the same animal bears both ova and sperm) or monoecious.

A monoecious plant produces male and female gametophytes in the same sporophyte, in constrast to dioecious plants, in which a single plant may have only either male or female organs. See Sexual reproduction of plants.

Monoecious - having unisexual flowers, conifer cones, or functionally equivalent structures of both sexes appearing on the same plant;
Dioecious - having unisexual flowers, conifer cones, or functionally equivalent structures occurring on different individuals;
Because many dioecious conifers show a tendency towards monoecy (that is, a female plant may sometimes produce small numbers of male cones or vice versa), these species are termed subdioecious.

[edit] Bryophyte sexuality

Bryophyte are generally gametophyte-oriented; that is, the normal plant is the haploid gametophyte, with the only diploid structure being the sporangium in season. As a result, bryophyte sexuality is very different from that of other plants. There are two basic categories of sexuality in bryophytes:

Monoicous bryophytes produce both antheridia (male organs) and archegonia (female organs) on the same plant body.
Dioicous bryophytes produce only antheridia or archegonia on a single plant body.

Some bryophyte species may be either monoicous or dioicous depending on environmental conditions. Other species grow exclusively with one type of sexuality.

Occasionally the terms "monoecious (dioecious)" and "monoicous (dioicous)" may be used interchangeably, but there is a tencency to restrict monoecious and dioecious only to seed plants, which refer to whether or not an individual sporophyte plant bears one or both kinds of gametophyte.