What does oocyte mean?
An oocyte is a female reproductive cell, commonly understood as an immature egg. It develops within the ovary through stages known as oogenesis, and in mammals it passes through meiosis to become a mature ovum capable of being fertilized. The term is especially common in reproductive biology and reproductive medicine, where researchers discuss the number, quality, maturation, and retrieval of oocytes. In assisted reproduction, for example, oocytes may be collected and fertilized in vitro. Calling a cell an oocyte emphasizes that it is a developing form of the female gamete rather than simply a general egg cell. The word is primarily technical, but its definition makes it a useful example of how biological vocabulary distinguishes stages in a cell’s development.
nounA female reproductive cell, or gamete, that develops into an ovum and may be fertilized during reproduction. In mammals, an oocyte is the immature egg cell formed in the ovary.
- A female reproductive cell that develops into an ovum and participates in fertilization.
"The oocyte is released from the ovary and travels through the fallopian tube, where fertilization may occur."
"The researcher examined the oocytes under a microscope to evaluate their maturation."
"After fertilization, the oocyte begins a series of divisions that can produce an embryo."
The plural is standard in biological and medical writing.
"Several oocytes were examined for abnormalities."
An oocyte is an egg cell before its final maturation: a microscopic starting point for new life that contains the genetic material from one parent.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does oocyte come from?
The word oocyte combines the Greek root ōon, meaning “egg,” with the combining form -cyte, meaning “cell.” The related term oogenesis names the process by which female reproductive cells develop. Its close biological and etymological relatives include ovum, the mature female gamete, and ovarian, referring to the ovaries where oocytes develop.
How oocyte is actually used
The term is used mainly in biology, reproductive medicine, and embryology. It is more technical than the general terms “egg” and “egg cell,” and is often used when referring to an immature female gamete or to the stages of oocyte development.
Easily confused with oocyte
An oocyte is the developing female reproductive cell, whereas an ovum is the mature female gamete, typically after meiotic maturation.