oocyte

IPA/ˈəʊ.ə.saɪt/
IPA/ˈoʊ.oʊ.saɪt/

oocyte — noun

  • oocytesingular
  • oocytesplural

1. a cell inside the ovary of a female animal or human that has not yet finished gr

1.nounC2
Definition

a cell inside the ovary of a female animal or human that has not yet finished growing, but later becomes a mature egg ready to join with a sperm.

Example

Mizuki studies how oocytes in mouse ovaries divide during the early stages of growth.

subject is a researcher; oocyte as countable plural in a biology context

The clinic froze twelve oocytes from Adina before her cancer treatment began.

collocation: freeze oocytes (fertility preservation context)

Common collocations
  • mature oocyte
  • freeze oocytes
  • collect oocytes
  • oocyte donation
Synonyms
  • egg cell

    everyday term; less precise — usually means the mature ovum

  • ovum

    the mature stage after the oocyte finishes dividing

Antonyms
  • spermatocyte

    the male equivalent — an immature sperm-producing cell

Usage Note

Almost always found in medical, scientific, or fertility-treatment contexts; in everyday speech, people say 'egg' or 'egg cell' instead. Often used in the plural.

Common Mistakes

The chicken laid three oocytes this morning.
The chicken laid three eggs this morning.
'oocyte' refers to the immature cell inside the body, not the laid egg you eat or hatch.

Word family

  • ovum
    nounC2
  • oogenesis
    nounC2
  • ovary
    nounB2
  • ovarian
    adjectiveC1

Synonym discussion

Sense: noun/1

These words all relate to female reproductive cells but mark different stages or contexts. An 'oocyte' is the immature cell still developing inside the ovary; it has not yet completed the divisions needed to be ready for fertilisation. Once those divisions finish, the same cell is called an 'ovum' — the mature egg that can join with a sperm. 'Egg cell' is the everyday English label that covers both stages loosely; it appears in school textbooks and general writing, while 'oocyte' and 'ovum' are reserved for medical, clinical, or scientific use. 'Ovule', confusingly similar, belongs to plant biology — it is the structure inside a flower that becomes a seed. A fertility doctor would say 'we collected fifteen oocytes'; a high-school teacher would say 'the egg cell travels down the tube'; a botanist would say 'the ovule develops into a seed'.

oocyte ↗ovum ↗egg cellovule

Common collocations

Nouns

  • oocyte donation
  • oocyte retrieval
  • oocyte maturation
  • oocyte quality

Phrases

  • freeze one's oocytes
  • collect oocytes for IVF

Prepositions

  • of (the ovary)
  • from (the donor)

Etymology

GreekScientific LatinEnglish

Formed in late nineteenth-century scientific English by joining the Greek root 'ōion', meaning 'egg', with '-cyte', from Greek 'kytos' meaning 'hollow vessel' or 'cell'. The combining form '-cyte' became a standard suffix for naming biological cells (compare 'leukocyte', 'lymphocyte', 'erythrocyte'), and 'oocyte' was coined specifically to name the immature egg cell as cell biology developed.