What does fertilised mean?
Fertilised is the past tense and past participle of the verb to fertilise, meaning either to make something fertile — typically enriching soil for cultivation — or, in biology, to cause an egg to begin development by uniting it with sperm or pollen. The word appears most often in scientific, medical, agricultural, and reproductive contexts: one speaks of a fertilised egg, freshly fertilised soil, or artificially fertilised embryos. As a participial adjective, 'a fertilised ovum' marks the very starting point of life in sexually reproducing organisms. The term is neutral and technical in register rather than emotive, which makes it useful for precise discussion in medicine and science. Spelled with -is- in British and Commonwealth English, it takes the form 'fertilized' in American usage; the two are the same word, differing only in orthography. Its Latin root fer, meaning 'to bear or carry', links it to the adjective fertile and its many derivatives.
Past tense and past participle of fertilise: to introduce sperm or pollen into an egg or ovum so that it begins development; to make soil or land fertile.
"The botanist fertilised the flowers by hand to guarantee cross-pollination."
In British English the spelling is fertilised; American English writes fertilized.
Describing an egg, ovum, or seed that has been successfully fertilised, or land that has been enriched to support growth.
"Only a single fertilised embryo was transferred during the IVF procedure."
This participial use is common as a premodifier in medical and biological writing.
Every one of us began as a single fertilised cell smaller than a full stop — about 0.1 millimetres wide.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of fertilised
Fertilised derives ultimately from the Latin verb fertilis ('fruitful, productive'), formed on ferre, 'to bear or carry'. The English adjective fertile entered via Old French in the fifteenth century, and the verb fertilise arose in the seventeenth century as part of the broader pattern of forming verbs from adjectives with the -ise suffix, itself borrowed through French from Latin -izare. Cognates include the French féconder-derived family and the Latinate fertilis lineage shared by words such as fertiliser and fertilisation.
Related word forms
How fertilised is actually used
'Fertilised' functions chiefly as the past tense and past participle of 'fertilise' and commonly as a participial adjective ('a fertilised egg'). It carries a neutral-to-scientific register, appearing most often in biology, medicine, agriculture, and reproductive-health contexts. The spelling with -is- is standard in Britain, Australia, and other Commonwealth countries; American English uses 'fertilized'. When describing people, note that 'pregnant' refers to the state after implantation, while 'fertilised' applies strictly from conception until implantation.
Easily confused with fertilised
'Fertilized' with a z is simply the American spelling of the same word; 'fertilise/fertilised' with s is the British spelling.
A fertiliser is a substance added to soil to enrich it, whereas fertilised describes something that has been made fertile or has had an egg united with sperm.