What does oogamy mean?
Oogamy is a form of sexual reproduction distinguished by a sharp difference in the size and behavior of the reproductive cells. The female gamete, or egg, is comparatively large, rich in nutrients, and normally non-motile, while the male gamete is smaller and actively swims toward it. This arrangement contrasts with isogamy, in which the gametes are essentially alike, and with the broader category of anisogamy, in which gametes differ in size. Oogamy is especially associated with reproduction in animals and many plants. Its terminology emphasizes the specialized roles of the two gametes: one provides most of the cellular material and remains stationary, while the other is adapted for movement and fusion. Although uncommon in general conversation, the term is useful in biology when describing reproductive structures, life cycles, and evolutionary transitions among sexual-reproduction systems.
nounA form of sexual reproduction in which the female gamete is large and non-motile, while the male gamete is smaller and motile. It is also the process by which such gametes fuse.
- A form of sexual reproduction in which the female gamete is large and non-motile and the male gamete is smaller and motile.
"Oogamy allows a large, nutrient-rich egg to remain stationary while a small sperm cell swims to it and fertilizes it."
"The reproductive cycle of the organism includes both oogamy and a distinctive form of asexual reproduction."
"Researchers studying the evolution of aquatic species used oogamy as evidence of increasing specialization between male and female gametes."
The plural is rare because the word is normally used in singular technical contexts.
"The article compares oogamies found in different groups of aquatic organisms."
Oogamy puts the romance in reproduction: the egg stays put while the sperm does the traveling.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does oogamy come from?
The word was formed in New Latin from Greek ᾠόν (ōíon), meaning “egg,” and γάμος (gámos), meaning “marriage” or sexual union. Its relatives include ovum, ovule, oogenesis, and gamete, all reflecting the same Greek reproductive vocabulary. The combination describes the union of a large egg with a smaller male gamete.
Related word forms
How oogamy is actually used
This is a technical biological term used chiefly in reproductive biology, botany, zoology, and evolutionary studies. It describes a specialized form of anisogamy rather than all reproduction involving unequal-sized gametes.
Easily confused with oogamy
Isogamy involves male and female gametes that are essentially identical in size and form, whereas oogamy involves a large egg and a much smaller, motile sperm.
Anisogamy describes the general condition of gametes differing in size, while oogamy is the more specialized form in which the larger female gamete is typically non-motile and the smaller male gamete is motile.