What does unfertilised mean?
Unfertilised is an adjective meaning that an egg or ovule has not been fertilised, usually by the fusion of male and female reproductive cells. It is especially associated with reproductive biology, embryology, and assisted-reproduction research, where researchers may examine whether an unfertilised egg remains viable or begins to develop under particular laboratory conditions. The word is also used more generally in discussions of biological processes, but it should not be confused with infertile, which describes a broader lack of reproductive capacity. British English normally uses the spelling with -s, while American English commonly writes unfertilized. The term is precise and technical rather than colloquial, and its value lies in distinguishing a particular pre-fertilisation state from other forms of reproductive failure. Its clearest established use is in phrases such as unfertilised egg and unfertilised ovum.
adjectiveNot fertilised; specifically, an egg or ovule that has not been fertilised by sperm.
- Not fertilised; an egg or ovule that has not been fertilised by sperm.
"The unfertilised egg remained viable until it was exposed to the appropriate hormones."
"Researchers placed the unfertilised egg into a culture medium for further testing."
"In the discussion of reproductive biology, the speaker distinguished an unfertilised ovum from a fertilised embryo."
Before fertilisation, an egg carries the potential for a new life—but biology has a precise word for that unfinished possibility.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does unfertilised come from?
Unfertilised is formed in English by adding the prefix un-, meaning “not,” to the British-spelled form fertilised. Fertilised derives from fertilise, ultimately from Latin fertilis, meaning “fertile” or “fruitful,” a term associated with ferre, “to bear” or “bring forth.” The modern word therefore combines the sense of fertility with an explicit negation.
How unfertilised is actually used
Chiefly used in biology and reproductive science. The -s spelling is standard in British English, while US English generally uses -z. It is more precise than infertile when describing the specific state of an egg or ovule rather than a general inability to reproduce.
Easily confused with unfertilised
Infertile describes something unable to reproduce or support reproduction, whereas unfertilised describes an egg or ovule that has not undergone fertilisation.
Unfertilized is the American spelling of the same word; unfertilised is the usual British spelling.